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AP BIOLOGY
Nichoel D'Alessio
a _
GET A HIGHER SCORE IN LESS TIME
- Acomplete AP Biology course in a concise, time-saving format
it - Targeted review covers only material that will actually be tested
- Strategies for answering every type of question
- Free online practice exam pinpoints your strengths and weaknesses
GREEN
“APs oregisteed trademark fhe Coleg Bord wich ws atinaved inthe prodction EDITION |
of and dos nat endorse this product,REA: THE TEST PREP AP TEACHERS RECOMMEND
AP BIOLOGY
CRASH COURSE
By Michael B’Alessio
Watchung Hills Regional High School
Warren, New Jersey
Research & Education Association
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AP BIOLOGY CRASH COURSE
Copyright © 2011, 2010 by Research & Education Association, Inc.
All rights reserved. No part of this book may be reproduced in
any form without permission of the publisher.
Printed in the United States of America
Library of Congress Control Number 2010940972
ISBN-13: 978-0-7386-0662-0
ISBN-10: 0-7386-0662-6
= REA® is a registered trademark of
Research & Education Association, Inc.
uoAP BIOLOGY
CRASH COURSE
Begin Reading
Table of Contents
Copyright Page
Access Your ExamAP BIOLOGY
CRASH COURSE
TABLE or CONTENTS
About This Book.
About Our Author.
Acknowledgments
[Gy INTRODUCTION
UE Chapter 1: Keys for Success on the AP Biology Exam,
FyVy] MOLECULES AND CELLS: CHEMISTRY OF LIFE,
A CELLS, AND CELLULAR ENERGETICS
Chapter 2: Water...
Chapter 3: Organic Molecules in Organisms...
Chapter 4: Free Energy Changes....
Chapter 5: Enzymes...
Chapter 6: Prokaryotic and Eukaryotic Cells
Chapter 7: Membranes....
Chapter 8: Subcellular Organization .....
Chapter 9: Cell Cycle and Regulation...
Chapter 10: Coupled Reactions.....
Chapter 11: Fermentation and Cellular Respiration ..
Chapter 12: Photosynthesis.AP Crash Course
[yy] HEREDITY AND EVOLUTION:
fal HEREDITY, MOLECULAR GENETICS
AND EVOLUTIONARY BIOLOGY
PART
Chapter 13:
Chapter 14:
Chapter 15:
Chapter 16:
Chapter 17:
Chapter 18:
Chapter 19:
Chapter 20:
Chapter 21:
Chapter 22:
Chapter 23:
Meiosis and Gametogenesis ...
Eukaryotic Chromosomes.....
Inheritance Patterns...
RNA and DNA Structure and Functiot
Gene Regulation...
Mutation...
Viral Structure and Replication,
Bacterial Gene Regulation...
Nucleic Acid Technology and Applications........ 91
Early Evolution of Life ...
Evidence for Evolution ..
Mechanisms of Evolutio1
ORGANISMS AND POPULATION: DIVERSITY
OF ORGANISMS, STRUCTURE AND FUNCTION
OF PLANTS AND ANIMALS, ECOLOGY
Chapter 24: Evolutionary Patterns... Ww
Chapter 25: Survey of the Diversity of Life . 115
Chapter 26: Phylogenetic Classification... 121
Chapter 27: Evolutionary Relationships ... 2125
Chapter 28: Plants and Animals—Reproduction,
Growth, and Development...
Chapter 29: Plants—Structural, Physiological,
and Behavioral Adaptations...
Chapter 30: Animals—Structural, Physiological,
and Behavioral Adaptations..... p35)
Chapter 31: Plants—Response to the Environment............ 147Table of Contents
al
i
Chapter 32:
Chapter 33:
Chapter 34:
Chapter 35:
Chapter 36:
THE EXAM
Chapter 37:
Chapter 38:
Chapter 39:
Biosphere ... ar
Population Dynamics.
Communities and Ecosystems...
Ecology—Behavior .
Ecology—Global Issues
Major AP Biology Themes and Their
Relationship to the Exam
The 12 AP Biology Labs . 175
Essay Writing—Exemplars, Data
Analysis /Graphing Techniques,
Setting Up an Experiment... .. 203About This Book
HE asout THis Book
REA's AP Biology Crash Course is the first book of its kind for the last-
minute studier or any AP student who wants a quick refresher on the
course. The Crash Course is based upon a careful analysis of the AP
Biology Course Description outline and actual AP test questions.
Written by an AP teacher, our easy-to-read format gives students a
crash course in Biology. The targeted review chapters prepare stu-
dents for the exam by focusing on the important topics tested on the
AP Biology exam.
Unlike other test preps, REA’s AP Biology Crash Course gives you areview
specifically focused on what you really need to study in order to ace
the exam. The review chapters offer you a concise way to learn all the
important facts, terms, and biological processes before the exam.
The introduction discusses the keys for success and shows you strate-
gies to help you build your overall point score. Parts Two, Three, and
Four are made up of our review chapters. Each chapter presents the
essential information you need to know about Biology.
Part Five focuses exclusively on the format of the AP Biology exam.
Each chapter in this section explains a specific aspect of the test,
including Major AP Biology Themes and Their Relationship to the
Test, the 12 AP Biology Labs, and Essay Writing (exemplars, data
analysis/graphing techniques, setting up an experiment).
No matter how or when you prepare for the AP Biology exam, REA’s
Crash Course will show you how to study efficiently and strategically,
so you can boost your score!
To check your test readiness for the AP Biology exam, either before or
after studying this Crash Course, take our FREE online practice exam.
To access your free practice exam, visit www.rea.com/crashcourse and
follow the on-screen instructions. This true-to-format test features
automatic scoring, detailed explanations of all answers, and will help
you identify your strengths and weaknesses so you'll be ready on
exam day!
Good luck on your AP Biology exam!
vilAP Crash Course
ABOUT OUR AUTHOR
Michael D’Alessio earned his BS in Biology from Seton Hall Univer-
sity, South Orange, New Jersey, and his MS in Biomedical Sciences
from the University of Medicine and Dentistry of New Jersey. In 2004,
he earned his Executive Master of Arts in Educational Leadership from
Seton Hall University.
Mr. D‘Alessio has had an extensive career teaching all levels of math-
ematics and science, including AP Biology, chemistry, physics, algebra
and geometry. Most of Mr. D’Alessio’s AP Biology students received
scores of 4 or 5 on the AP Biology exam.
Currently, Mr. D’Alessio serves as the Supervisor of the Mathematics
and Business Department at Watchung Hills Regional High School in
Warren, New Jersey, overseeing a department of 30 teachers. In addi-
tion, Mr. D’Alessio participates in numerous SAT workshops around
the country, preparing students for the mathematics portion of the
test.
In 2003, Mr. D’Alessio received the Governor's Teacher of the Year
recognition for Watchung Hills Regional High School. In 2004, Mr.
D’Alessio received a Certificate of Recognition of Excellence in Sci-
ence Teaching from Sigma Xi, the Scientific Research Society of Rut-
gers University and in 2005, he was voted National Honor Society
Teacher of the Year by the students of Watchung Hills.
Mr. D’Alessio would like to thank Larry Krieger for encouraging him
to write this AP Biology Crash Course and Dr. Jeffrey Charney for his
invaluable help in proofreading and editing the manuscript.
ACKNOWLEDGMENTS
In addition to our author, we would like to thank Larry B. Kling, Vice
President, Editorial, for his overall guidance, which brought this pub-
lication to completion; Pam Weston, Publisher, for setting the qual-
ity standards for production integrity and managing the publication
to completion; Diane Goldschmidt, Senior Editor, for editorial proj-
ect management; Alice Leonard, Michael Reynolds, and Kathleen
Casey, Senior Editors, for preflight editorial review; Rachel DiMatteo,
Graphic Artist, for page design; and Weymouth Design for designing
our cover.
We also extend our thanks to Rebekah Warner for technically editing
the manuscript, Ellen Gong for proofreading, and Kathy Caratozzolo
of Caragraphics for typesetting this edition.
viiiPART I:
INTRODUCTIONKeys for Success on the
AP Biology Exam
AP Biology textbooks are very thick and contain thousands of bio-
logical facts and concepts. if the AP Biology exam contained all
of these facts, the challenge to earn a good score on the exam
would be daunting. Studying for this exam requires the student
to be a pragmatic learner who can delineate the important tested
material from the material that is “interesting to know.”
This book will help you become more pragmatic in your studying
and streamline your chances to score a 4 or 5 on this exam. The
keys to success on the exam include knowing the following:
1. The Content of the Advanced Placement Biology
Examination
The Advanced Placement Biology curriculum is based on the
content of an introductory biology course taught at the col-
lege level. The topics taught in the class reflect major themes
that are presented in a number of college-level textbooks.
The curriculum of the course also includes 12 thematic-based
laboratories. The underpinnings of these labs are based on
common biological tenets that are taught in the course. In
order to succeed on the exam, students need to master the
basic concepts of biology and apply these concepts to vari-
ous situations in a traditional test format. The make-up of the
exam is based on the following percentages in three topics of
understanding:
|. Molecules and Cells, 25%
Il. Heredity and Evolution, 25%
Ill, Organisms and Populations, 50%
3
JaydeydChapter 1
The AP Biology examination is 3 hours in length, consisting
of an 80-minute, 100 multiple-choice-question section and
a 90-minute, free-response section with 4 essays. You are given
a 10-minute reading period in which you may read the essay
questions and outline a format to respond to the questions.
Part |. 80 minutes, 100 multiple-choice questions = 60% of
the grade
The number of multiple-choice questions from each topic is
based on the percentages above. For example, expect the fol-
lowing:
25 multiple-choice questions pertaining to Molecules
and Cells
25 multiple-choice questions pertaining to Heredity and
Evolution
50 multiple-choice questions pertaining to Organisms
and Populations
Part Il. 90 minutes, 4 essay free-response section = 40% of
the grade
One essay will be from Topic |, Molecules and Cells
One essay will be from Topic Il, Heredity and Evolution
Two essays will be from Topic Ill, Organisms and Populations
One or more of these essays could require you to interpret sci-
entific data from one of the 12 required AP laboratories. Each
free response is weighted equally, and you must answer them
in essay form (outlines are not acceptable).
Process- vs. Content-Based Questions
Content-based questions are simply designed in order to test
your ability to know and recall facts about a particular topic.
For example, below is a multiple-choice question on cell res-
piration:
In cell respiration, glucose is converted to pyruvate in
which of the following metabolic pathways?
(A) Gluconeogenesis
(B) Krebs cycleKeys for Success on the AP Biology Exam
(©) Glycolysis
(D) Light Dependent Reaction
(E) Oxidative Phosphorylation
The correct answer is (C). Glycolysis is a ten-step anaerobic
pathway that converts glucose (6 carbon sugar) to 2 pyruvate
molecules (3 carbon atoms each).
The good news is that content-based questions make up a
good portion of the AP exam. It is essential to know these ba-
sic ideas when confronted by this type of question. This book
will give you the content you need to know in a Crash Course
manner.
Process-based questions are designed for you to apply the
content you have learned to a situation. You should not be
intimidated by these types of questions, because knowing
the content goes a long way in helping you determine the
correct answer. The questions tend to be in the laboratory/
experimental-based questioning part of the exam. It is crucial
for you to know what should have been interpreted and con-
cluded in the 12 AP labs. Below is an example of a process-
based question:
A biologist prepares an in vitro sample of the activity of
the enzyme protease, which promotes the hydrolysis
of proteins to amino acids. Three flasks containing 20
milliliters of 5% hemoglobin (a protein) in water are
prepared with the addition at time zero of each of the
substances indicated in the diagram below.
I mL protease Tmtwater mC botted provease
/ \ i i. \
/ \ fi \ / \
/ 596 hemoglobin / s%hemagiabin \, / 5% hemoglobin \,
\ ¢ s )
FLASK A FLASKB FLASK C
5Chapter 1
In the experiment above, which flask(s) would you ex-
pect hemoglobin molecules to maintain a higher-level
protein structure?
(A) Flask A
(B) Flask B
(C) Flask C
(D) Flasks A and B
(E)_ Flasks B and C
The correct answer is (E). Water is the control, and boiled pro-
tease will have lost its enzymatic activity because of enzymatic
denaturation. The content to apply to correctly answer this
process-based question is the definition of a controlled experi-
ment and physical properties of enzymes.
The good news is that process-based questions make up a
smaller portion of the AP exam when compared to content-
based items. This Crash Course will help you know the con-
tent needed for making the process-based questions easier to
handle.
Expect to see multiple-choice questions in the following
formats.
Type |. Traditional multiple-choice questions with choices
(A) through (E). There is only one correct answer!
Which of the following is MOST inclusive when clas-
sifying organisms using taxonomy?
(A) Domain
(B) Kingdom
(C) Phylum
(D) Class
(E) Order
The answer is (A). Domain includes the most organisms within
a particular group.Keys for Success on the AP Biology Exam
Type Il. Heading multiple-choice questions with choices (A)
through (E). There is only one correct answer for each ques-
tion. However, the answers could be used in a set of questions
once, more than once, or not at all.
Questions 70-74
(A) Immune System
(B) Nervous System
(© Digestive System
(D) Circulatory System
(E) Excretory System
70. Involves blood that is oxygenated
7 Enzyme called amylase is an important part of
this system
72. Involved in allergic attacks
73. Basic unit is called the nephron
74. Peristalsis is a key type of action
Answers
70. D 71. 72. A 73. E 74. C
How Is the Test Scored?
Section I. Total scores on the multiple-choice section of the
exam are based on the number of questions answered cor-
rectly. Points are not deducted for incorrect answers and no
points are awarded for unanswered questions.
Multiple-Choice Raw Score
Number Right x .90 =
Weighted Score
for Section |
7Chapter 1
Section Il. The free-response section is scored by multiply-
ing the number of raw points earned on each essay by 1.50.
x 1.50 =
(possible points
out of 10)
Free-Response Question 1
x 1.50 =
(possible points
out of 10)
Free-Response Question 2
x 1.50 =
(possible points
‘out of 10)
Free-Response Question 3
x 1.50 =
Free-Response Question 4 ___
(possible points J
out of 10)
Combined Free-Response Score =
Composite Score = (MC Weighted Score)
+ (Combined Free-Response Score)
Composite Score Range* | AP Grade
95-150 5
81-94 4
69-80 3
58-68 &
0-57 1
* From the 2009 released exam. Composite score
ranges change year to year.
On the low end you can score 95 out of a possible 150 points
(63%) and STILL earn a 5 on the test. To earn a 4 you need 81
points out of a possible 150, or just 54%!!! This Crash Course
will help you achieve the highest grade possible on this test.Keys for Success on the AP Biology Exam
4, What Is the Breakdown of AP Biology Grades Across the
United States?
% of Students Earning Examination Grade of
Year 5 4 3 2 1
2006 19.6% | 20.3% | 21.2% | 23.3% | 15.6%
2007 19.3% | 20.3% | 21.2% | 23.2% | 15.9%
2008 | 18.6% | 15.6% | 16.1% | 15.2% | 34.6%
(Data obtained from College Board Student Grade Distribution Reports,
2006-2008.)
The data above indicates that about one out of five of the stu-
dents who take the AP Biology Examination earned a 5, with
a staggering 34.6% of students earning a 1 in 2008. In 2008,
there were 154,000 test takers for AP Biology, which was an
all-time high. This Crash Course is tailored for all of the stu-
dents represented in the data and will help you earn a grade
that will allow you to receive college credit for biology.
5. Using College Board and REA Materials to Supplement
Your Crash Course
Your Crash Course contains everything you need to know to
score a4 or 5. You should, however, supplement it with materi-
als provided by the College Board and other resources. The AP
Biology Course Description Booklet, and the 1999, 2002, and
2008 released AP Biology exams, can all be ordered from the
College Board’s Online Store (http://store.collegeboard.com).
In addition, the College Board’s AP Central site (http://apcentral.
collegeboard.com) contains a wealth of materials, including
essay questions with exemplars and rubrics. And finally, REA’s
AP Biology (7th Edition) contains excellent narrative chapters
that supplement this Crash Course material.
9——— PART II:
MOLECULES AND CELLS:
Chemistry of Life,
Cells, and Cellular
EnergeticsWater
Chemistry of Life—Water
A. The Amazing Properties of the Water Molecule
1.
Water is a polar molecule; this means it is a molecule whose
ends have opposite charges (hydrogen being positive and
oxygen being negative).
. Hydrogen bonding—the ability of hydrogen to interact with
the elements fluorine, oxygen, and nitrogen. This is not a
covalent bond.
. For every 1 water molecule, 4 more molecules can hydrogen-
bond with the original.
.. Most abundant molecule in living organisms.
.. Water exhibits hydrogen bonding leading to the following
properties.
i. Cohesion—the ability of water molecules to stick together.
Example: the movement of water against gravity on plant
surfaces.
ii, Adhesion—the ability of water to adhere to molecules
other than water. Example: water moving through a hose
and adhering to the inside of the hose.
Surface Tension—the measure of how difficult it is to break
the surface of water. Example: the high surface tension of
water allows a water strider (skater) to walk on the surface
of a pond with minimal effort.
iv. Specific Heat—the amount of energy (heat) it takes to raise
or lower the temperature of one gram of a substance 1
degree Celsius. Water has a high specific heat; therefore,
large bodies of water do not evaporate easily.
13
JaydeydChapter 2
v. Evaporative Cooling—since water has a high heat of
vaporization, once water leaves a surface, the surface
cools down. Example: the sweat of an athlete assists in
maintaining homeostasis during a vigorous workout.
B. Dissociation of Water (or the shifting of hydrogen from one
water molecule to another)
1, 2H,O <> H,O* (hydronium ion) + OH" (hydroxide ion)
2. The counterbalance of hydronium and hydroxide results with
a pH of 7.0 for water.
3. Acid (biological definition)—a molecule that increases
hydronium concentration.
Example: HCl > Ht + Cl
4, Base (biological definition)—a molecule that increases
hydroxide concentration.
Example: NaOH - Na* + OH-
5. pH scale—ranges from 0-14, with 7 being neutral. Each
increment of 1 on the pH scale is a ten-fold change.
6. The deleterious effects of acid rain—production of carbon
dioxide and sulfur oxides from industrial manufacturing leads
to the production of acidic conditions (H,CO, and H,SO,).
Acid rain affects ecosystems such as lakes and forests.
Molecules and Cells—Inquiry about the amazing properties
of water has been expanded in AP Biology essays. Water is a
recurring theme found in all aspects of molecules and cells.Organic Molecules
in Organisms
Chemistry of Life—Organic Molecules in Organisms
A. Organic Chemistry—the study of carbon-containing compounds
1.
Carbon is the building block of the four major
macromolecules: carbohydrates, lipids, proteins, and nucleic
acids.
. Tetra-valence or the ability to form 4 covalent bonds is a
hallmark of the carbon atom.
B. Functional Groups—groups of accessory elements that attach to
molecules that give them a different structure, and thus a different
function
1.
Hydroxyl Group—hydrogen bonded to oxygen attached
to a carbon skeleton. Molecules with hydroxyl groups are
considered alcohols.
—oH
HYDROXYL
. Carbonyl Group—carbon joined to oxygen via a double bond.
If the carbonyl group is on the end of a carbon skeleton, it
is called an aldehyde; otherwise the compound is called a
ketone.
0 0
I I)
c c
aS x
H
ALDEHYDE KETONE
15
JaydeydChapter 3
. Carboxyl Group—carbon is doubled bonded to an oxygen
and a hydroxyl (carboxyl is a combination of carbonyl and
hydroxyl)
0
|
¢
as
oH
CARBOXYLIC ACID
. Amino Group—a nitrogen atom bonded to two hydrogen
atoms and one carbon. Amines are organic molecules that
contain an amino group.
Ni,
)
.. Phosphate Group—a phosphate ion covalently attached to
a carbon skeleton. Phosphate groups have a tremendous
amount of energy associated with them.
PHOSPHATE
C. Biologically Important Molecules
1
Macromolecules—large molecules that fall into four categories:
carbohydrates, lipids, proteins, and nucleic acids (see the
molecular genetics chapter).
. Polymer—a long molecule consisting of similar molecules
held together by covalent bonds. (Poly = many)
. Monomers—the repetitive molecules of a polymer.
(Mono = one)
. The synthesis of polymers takes place through a reaction
called dehydration synthesis (condensation reaction). In this
reaction water is lost.Organic Molecules in Organisms
» =
| Ny
i
Ho— 4
5. The breakdown of polymers takes place through a reaction
called hydrolysis. In this reaction water is added across the
covalent bond. (Hydro = water, lysis = break)
HO. H
| 2
Ho
HO -—H
D. Carbohydrates
1. Definition: sugar and the polymers of sugar. Ending with
suffix -ose. 45-65% of dietary allowance. 4 calories per gram.
Excess carbohydrates can be converted to fat.
2. Monosaccharide—single sugars with a formula of CH,O.
3. Most important monosaccharide is glucose. C,H,,O,.
—CH,0H Hon
of 09H
A :
\ VA
on H
a Ou OH
‘Alpha (cx) Glucose Beta (B) Glucose
Difference is hydroxyl on carbon 1.
17Chapter 3
18
4. Disaccharides—two monosaccharides linked via dehydration
synthesis.
5. Glycosidic bond is the covalent bond formed between
monosaccharides to form di- and polysaccharides.
. Maltose—glucose/glucose disaccharide.
. Sucrose—glucose/fructose disaccharide.
. Lactose—glucose/galactose disaccharide.
. Polysaccharides—macromolecules with 100-1000 of
monomer subunits.
i. Storage Polysaccharide—starch for plants. Glycogen
for animals.
ii. Structural Polysaccharide—cellulose for plants (indigestible
for humans). Chitin found in arthropods and fungi.
COND
. Lipids (Fats/Triglycerides, Phospholipids, Steroids)
1. The only class of large molecules that are not considered
polymers.
2. Lipids are hydrophobic—fear of water.
3. Used for insulation and buoyancy in marine and Arctic
animals.
4. Major component of membranes.
5. fat or triglyceride—glycerol and 3 fatty acids.
9 Calories per gram, thus making it the most energy rich
of the biologically important compounds. 10-35% of
dietary allowance.
ii, Too much fat causes a build-up in the arteries called
atherosclerosis.
iii, Fatty Acids—long chains of carbon attached to a carboxyl
group.
iv. Saturated Fatty Acids—no double bonds between carbon
atoms. Example: Animal fat—lard or butter (solids at room
temperature).Organic Molecules in Organisms
v. Unsaturated Fatty Acid—has some double bonds between
carbon atoms, Example: Plant and fish fat and many
vegetable oils (liquids at room temperature).
°
6. Phospholipids—are lipids but unlike triglycerides only have
2 fatty acids.
i, Glycerol + phosphate + 2 fatty acids = a phospholipid.
ii, Head region contains the glycerol and phosphate and
is hydrophilic (attracted to water).
iii, Tail region contains the fatty acids (1 saturated and
1 unsaturated) and is hydrophobic.
iv, Phospholipids are the basic units of biological membranes.
} Hydrophilic Head
ydrophobic Tail
7. Steroids—tipids that consist of 4 fused rings.
i. Structure of the precursor lipid cholesterol.
is
H3C CH
cH
Ho
ii. Many steroid hormones in animals are produced from
cholesterol.
19Chapter 3
20
F. Proteins
1
Molecules that perform structural, catalytic, signaling,
defense, and transport duties within the cell. Make up about
50% of the dry weight of a cell. 4 calories per gram. 10-35%
of dietary allowance.
. Proteins are made up of monomer units called amino acids.
An amino acid consists of an amino group, a carboxyl
group, and up to 20 different side chain groups (20 different
amino acids) that give each amino acid unique physical
and chemical properties (different structure, thus a different
function).
R R= side chain
. Dipeptide is formed when two amino acids are linked via
dehydration synthesis.
. Peptide bond is the covalent bond formed between amino
acids.
. When many amino acids come together via dehydration
synthesis, a polypeptide is formed. Polymers of amino acids
are called polypeptides, and when one or more polypeptides
fold in specific conformations, a protein is formed.
. A protein conformation (shape) depends on 4 levels of
organization.
i, Primary Structure—unique sequence of amino acids.
ii. Secondary Structure—the interaction of hydrogen bonds
along the peptide chain forming an alpha (a) helix or beta
(A) pleated sheet.
Tertiary Structure—the interaction between the « helix
and f pleated sheet. Disulfide bridges, hydrophobic
interaction, hydrogen bonding, and Van der Waals forces
allow the structure to form.
iv. Quaternary Structure—the interaction of 2 or more
polypeptide chains forming a multi-subunit protein.
Examples include DNA polymerase, collagen, and
hemoglobin.Organic Molecules in Organisms
v. Denaturation—an inactive form of a protein (back to
primary sequence) can take place with changes to pH,
salt concentration, temperature, or exposure to toxic
compounds.
'. Protein homology—refers to the fact that certain proteins have
similar structures that are found in more than one species
that share a common ancestor. These proteins share a high
degree of amino acid correspondence. An example is the
cytochrome c protein found in the electron transport chain.
The data below indicates humans and rhesus monkeys are
closer on the evolutionary chain than humans and tuna.
Number of Amino Acid Differences
Species When Compared to Humans
Human 0
Rhesus monkey 1
Kangaroo 10
Snapping turtle 15
Bullfrog 18
Tuna 21
Molecules and Cells—Biologically important molecules are
great examples of the “structure and function” theme. Be sure
to use these examples in essay questions to gain critical points.
21Free Energy Changes
Chemistry of Life—Free Energy Changes
A. Metabolism—the totality of all chemical reactions that occur
within an organism.
B. Anabolic Reactions—sets of reactions that consume energy to
make molecules. For example, the synthesis of DNA or protein is
anabolic.
C. Catabolic Reactions—sets of reactions that produce energy in the
breakdown of molecules. For example, the breakdown of glucose
into carbon dioxide and water with the production of ATP.
D. Energy—capacity to do work.
E. 1* Jaw of thermodynamics—energy can neither be created nor
destroyed but can change from one form to another. Example:
Plants convert light energy from the sun to make chemical
energy in the form of glucose.
F. 2 law of thermodynamics—every energy transfer increases the
entropy of the universe (disorder).
G. Free Energy—the total amount of energy in a system (a cell) that
can be tapped to do work. Not all energy transfers are 100%.
H. Exergonic Reaction—a reaction that produces a net release of free
energy.
AB > A+B + Energy
23
JaydeydChapter 4
24
Endergonic Reaction—a reaction that absorbs free energy from its
surroundings.
A+B 4+ Energy > AB
Energy Coupling—using the products of an exergonic reaction
to help run an endergonic reaction. The molecule that is
essential for coupling of reactions and cellular work is adenosine
triphosphate (ATP).
Adenine
Phosphate Why
Groups i Arh
a eee
NH
OH OH
Ribose
When the terminal (last) bond of phosphate of ATP is broken
(via hydrolysis), energy is released (exergonic). Adenosine
diphosphate (ADP) is formed.
Hydrolysis of ATP
Po PH PonFree Energy Changes
The ATP cycle is the process in which ATP is hydrolyzed and ADP is
phosphorylated (addition of a phosphate group) to reform ATP.
AP
Phosphorylation Hydrolysis
ADP + Pi
SZ Molecules and Cells—ATP is used in a plethora of biological
situations including active transport, muscle movement, DNA
replication, and cell respiration/photosynthesis.
25Enzymes
Chemistry of Life—Enzymes
A. 99.9% of enzymes are proteins in structure. 0.1% are ribozymes
made of RNA (found in rRNA).
B. Enzymes are catalysts or biological chemical agents that speed up
a reaction without being consumed or produced by the reaction.
Most enzymes end with the suffix -ase.
C. An enzyme works by lowering the activation energy (E,) of a
reaction. Activation energy is defined as the amount of input
energy needed to start a chemical reaction.
ENERGY PROFILE FOR ENZYME
TRANSITION STATE
__— ACTIVATION ENERGY E,
> ENZYME LOWERS E,
FREE ENERGY ——>
\ Propucts
PROGRESS OF THE REACTION ——>
D. The enzyme combines with the substrate or molecule that the
enzyme will work on. When the enzyme and substrate
27
JaydeydChapter 5
28
are joined, a catalytic reaction takes place, forming a product.
The enzyme can be recycled and used for later reactions.
. Active site of the enzyme is the region that the substrate binds.
-. The catalytic cycle of an enzyme:
Enzyme + Substrate <> Enzyme — Substrate Complex <> Enzyme + Product
Induced Fit Model of Catalysis—the enzyme's active site and
substrate bind to each other, “inducing” a very slight change in
the structure of the enzyme, which promotes the reaction.
. Environmental factors that disrupt the activity of enzymes
include:
1. Each enzyme has an optimal temperature. If the temperature
is too high, the enzyme will denature (3-D shape will be lost).
If the temperature is too low, the enzyme will slow down.
2. Each enzyme has an optimal pH. If the pH is too high or too
low, the enzyme will denature.
3. Cofactor—non-organic molecules that augment enzyme
activity. Examples: iron, magnesium, and copper.
4. Coenzyme—organic molecule that augments enzyme activity.
Example: vitamins
|. Allosteric Site and Regulation—a portion of the enzyme in which
a regulator will bind. This is not the same as the active site. The
effect on the enzyme may be stimulatory or inhibitory.
Feedback Inhibition—when the end product of a biological
pathway inhibits the activity of an enzyme involved in that
pathway.
Cooperativity—different from allosteric regulation because the
enzyme contains multiple subunits. When a regulator binds
to one subunit, the other subunits “follow course” and a
conformational change in the enzyme’s shape takes place.
This has the effect of amplifying the activity of the enzyme.Enzymes
IMPORTANT ENZYMES TO KNOW
Enzyme
Lipase
Protease
DNAse
RNAse
Kinase
Carboxylase
Decarboxylase
Dehydrogenase
Substrate
Lipids
Proteins
DNA
RNA
Any molecule
Any molecule
Any molecule
Any molecule
Action
Breaks down lipids
Breaks down protein
Breaks down DNA
Breaks down RNA
Transfers phosphate
groups
Adds carbon dioxide
to create an additional
-COOH group
Removes carbon dioxide
Adds electrons and
hydrogen
Molecules and Cells—Knowing a list of enzymes and their
substrates is helpful in AP essays. Correctly naming an enzyme
and its substrate will translate to points on your essay.
29Prokaryotic and
Eukaryotic Cells
Cells—Prokaryotic and Eukaryotic Cells
A. Cytology—“cyto” meaning cell, “logy” meaning study of—is the
branch of biology that studies the structure and function of cells.
Microscopes are the instruments that allow the study of the
structure of a cell.
He
w
Light Microscope—based on light passing through a two-lens
system. Ocular lenses = 10x magnification, objectives lenses
= 4x, 10x, 40x, or 100x magnification. Total magnification =
ocular x objective. Can view prokaryotic and eukaryotic cells
from the light microscope, but not a virus.
.. Magnification—ability to enlarge the image.
. Resolution—ability to provide clarity to the image.
. Electron Microscope—uses a beam of electrons to provide
greater magnification and resolution.
i. Transmission Electron Microscope—used to view the internal
components of cells (organelles).
ii, Scanning Electron Microscope—used to view the surface of
cells.
. Cell Fractionation is the ability to use centrifuges
(ultracentrifuges) to spin at different high speeds to
“fractionate” (split apart) cells.
i. Homogenate (tear apart)—2 layers (pellet and
supernatant) — supernatant contains mitochondria and/or
chloroplasts — supernatant contains cell membrane and
internal membranes — supernatant contains ribosomes.
B. Prokaryotic CelH—unicellular bacteria.
ile
2.
Have no nucleus!!!
Generally considered the first form of life and were most
likely anaerobic.
31
JaydeydChapter 6
32
3. Nucleoid region—“devoid” of a true nucleus, but had DNA
floating in the cytoplasm. No nuclear membrane.
4. Cytoplasm—region between the nucleus and the plasma
membrane.
5. Cytosol—semi-fluid within the cell.
6. Generally 1 to 10 micrometers in size.
7. Have a cell membrane—regulates transport and is very
selective in permeability.
8. Have a cell wall—protective layer external to the cell
membrane. The cell wall does not contain phospholipids or
transmembrane proteins.
9. Contains ribosomes—location of protein synthesis.
10. Capsule—ties outside of the cell wall, made of carbohydrate,
and is pathogenic (disease causing).
C. Eukaryotic Cell—animal cell or plant cell; members are all
multicellular. There are unicellular eukaryotic cells (fungi).
1. Does contain a nucleus.
2. Nuclear envelope—double membrane made of phospholipids
and proteins. Maximum protection of the DNA in the
nucleus.
3. Nuclear pores—holes in the envelope that allow transport into
and out of the nucleus.
4. Nuclear lamina—set of proteins that give the nucleus
structure.
5. Chromatin—DNA and proteins combine within the nucleus.
Coiled DNA around proteins allows maximum occupancy of
the nucleus by DNA.
6. Chromosomes—coiled chromatin that contains genes.
7. Nucleolus—inside the nucleus and the location of where
ribosomes are synthesized. Stains dark using cell-staining
procedures.
8. Ribosomes—found outside of the nucleus and are the location
of the synthesis of proteins. (Common between both
prokaryotes and eukaryotes.)Prokaryotic and Eukaryotic Cells
Organelles Found in Animal
Cells but Not in Plant Cells
Centrioles
Lysosomes
Cilia
Flagella
Intermediate Filaments
Organelles Found in Plant
Cells but Not in Animal Cells
Cell Wall
Chloroplast
Central Vacuole
Plasmodesmata
Test &
Tip
6CO, + 6H,O + ATP
. Both involve oxidation-reduction reactions:
i, Loss of electrons is oxidation (glucose to carbon dioxide).
Gain of electrons is reduction (oxygen to water).
ili. Electrons = Energy
. In cell respiration there are two “electron and hydrogen
carrier molecules” that help carry the energy from glucose
to the mitochondria where it will be harnessed —NADH
(Nicotinamide Adenine Dinucleotide) and FADH, (Flavin Adenine
Dinucleotide).
i. NAD* = oxidized form, NADH = reduced form
ji. FAD = oxidized form, FADH, = reduced form
B. The Four Parts of Cellular Respiration
1.
Glycolysis— “splitting of sugar”
i, Takes place in the cytoplasm and is an anerobic process.
Oldest metabolic pathway since it is found in
prokaryotes, which were the first organisms on earth.
iii, The 6 carbon sugar, glucose, is broken down into two
3-carbon molecules called pyruvate. This is just a re-
arrangement of the carbons from glucose.
iv. Ten-step metabolic reaction that initially invests ATP that
will yield a “small” energy payoff.
|49
JaydeydChapter 11
50
v. NAD* is reduced to NADH.
vi. End products of glycolysis are 2 pyruvate molecules,
2 NADH molecules, and 2 ATP via substrate level
phosphorylation (2 of each molecule because of the
splitting of the glucose molecule in step 4).
Substrate level phosphorylation—formation of ATP via a
direct transfer of phosphate from a donor molecule to
ADP.
viii, There is no loss of CO, (decarboxylation) in glycolysis.
vii.
. Shuttle Step—“process of converting pyruvate to Acetyl CoA.”
i. Takes place in the mitochondria.
ii, Pyruvate is decarboxylated to form acetate a 2-carbon
compound. Acetate then has a coenzyme A group
attached to it to form Acetyl Coenyzme A (Acetyl-CoA).
NADH is made as a by-product via a reduction reaction.
Pyrvuate (3 carbons) 225, acetyl-CoA (2 carbons) + 2C0 +NADH
. Krebs Cycle—“generation of NADH and FADH,,”
i. Takes place in the mitochondrial matrix.
ii, Eight-step metabolic reaction that produces the majority
of NADH, FADH,, and CO, (waste product) for cellular
respiration.
Key intermediate to know: Oxaloacetate (OAA); the
2-carbon fragment from Acetyl Co-A is added to OAA to
make citrate.
Electron Transport Chain Coupled to Oxidative Phosphorylation
i. The inner mitochondrial membrane or cristae is the site
where Electron Transport Chain (ETC) proteins are found.
i. Proteins in the ETC accept electrons from the electron
carriers NADH and FADH,. The cytochrome complex is
a series of proteins in the ETC (evolutionary, conserved
through time).
Electrons get passed down the ETC via oxidation-
reduction reactions until they meet the final electron
acceptor molecule, oxygen (O,), to form HO.
iv, In the ETC, no direct ATP is made; it must be coupled
to Oxidative Phosphorylation via chemiosmosis (or the
diffusion of H* ions across the membrane).
Electron Transport Chain A255, oy dative PhosphorylationFermentation and Cellular Respiration
v. As NADH and FADH, are oxidized, H* inside the
mitochondrial matrix is transported to the intermembrane
space. A proton motive force (or storing of energy) is
created across the membrane due to this transport. Once
the H* is in the intermembrane space, it “leaks” back
through the membrane by using an enzyme called ATP
synthase and ATP is produced.
vi. Electrons that passed via NADH produce 3 ATP, while
electrons from FADH, produce 2 ATP.
Cellular Respiration Scorecard
Direct ATP from
Substrate-Level NADH FADH,
Step Phosphorylation | Produced | Produced
Glycolysis 2 2 0
Shuttle Step 0 af 0
Krebs Cycle 2 6 2
*Could be FADH, depending on the type of shuttle: 1 NADH = 3 ATP; 1 FAHD, = 2 ATP
ante roe
“ONADH x 3ATP = 30ATP —> seme <
2FADH2 X 2ATP = 4ATP THAN
C. Fermentation
le
Lactic Acid Fermentation—" anaerobic process in which only
glycolysis takes place.”
i. Takes place in prokaryotes and in humans.
ii, Pyruvate is converted to lactic acid producing only 2 ATP
and 2 NADH.
iii, Prokaryotes can only use fermentation (glycolysis) because
they have no mitochondria that are required for the other
parts of cellular respiration.
iv. In humans this anaerobic process (lack of oxygen to the
muscles cells) causes the phenomenon of “the burn” in
muscles cells. Vigorous exercise can cause lactic acid
build-up and therefore cause muscle pain and fatigue.
|51Chapter 11
cps
Giuase 2 2Pywate +2a1?
2NAD* 2NADH
2Lactate <—— 2 Pyrwate
2. Alcoholic Fermentation—“ anaerobic process in which only
glycolysis takes place.”
i. Takes place in fungi, such as yeast, and is used in the beer
and wine industry.
. Pyruvate is converted to acetylaldehyde and then ethanol,
producing only 2 ATP, 2NADH, and 2 CO,.
Fungi have mitochondria, but in anaerobic conditions
carry out this process.
Glucose 2", > pyruvate +241°
2NAD* 2NADH
2€thanol <———— 2 Acetyladehyde
\ =
Te St esa Molecules and Cells—Don't stress out to learn the names of
Tip/ all the enzymes involved in cellular respiration. AP questions
on this topic are designed for you to understand the “big
picture” of cell respiration.
52Photosynthesis
Cellular Energetics—Photosynthesis
A. Autotrophs/Heterotrophs
1.
4.
Used by autotrophs or “self feeders”—organisms that create
their own organic molecules or food. Autotrophs are also
known as producers.
. Plants are photoautotrophs—organisms that create their own
organic molecules or food by using light energy.
. Heterotrophs—organisms that cannot create their own
organic molecules or food. Heterotrophs are consumers.
Photosynthesis takes place in the chloroplast of the plant.
B. The two parts of photosynthesis
1.
Light Dependent Reaction—“process in which NADPH, ATP, and
O, are produced.”
i. Accessory molecules to know in the light-dependent
reaction:
* Chlorophyll a—absorbs red light (680 nm) and purple
light (400 nm).
* Chlorophyll b—absorbs yellow light (650 nm) and blue
light (450 nm).
* Carotenoids—absorbs at various wavelengths and
protects the chlorophyll molecules.
|. The accessory molecules absorb photons of light and
become “excited” when their electrons gain energy.
Photosystems—light-gathering centers that contain
chlorophyll and accessory molecules.
© Photosystem II—P680—named such because light is
absorbed best at 680 nm.
|53
JaydeydChapter 12
* Photosystem I—P700—named such because light is
absorbed best at 700 nm.
iv. Route of electrons though non-cyclic electron flow of the
light dependent reaction.
Photosystem IP 680 absorbs light and elections ae excited.
¥
Electrons in P680 are now “boosted toa higher level and must be replaced.
Water is split via light (photolysis) and the electrons are replenished:
[MOLECULAR oxygen is produced.
Y
Tl
Electrons pass down an electron transport chain similar tothe one found in
cellular respiration. Chemiosmasis takes place and ATP is produced.
Electrons are passed to Photosystem |-P700 where they are again boosted
toa higher level.
Electrons are then passed down a second election transport chain that
produces NADPH.
FINAL PRODUCTS OF LIGHT REACTION
0, via photolysis
AP via ETC
NADPH via ETC
v. Route of electrons through cyclic electron flow of the light-
dependent reaction.Photosynthesis
* This reaction takes place by electrons cycling back from
P700 through the first ETC. This has the net effect of
producing ATP in greater amounts. No NADPH or O, is
produced. This reaction takes place because the Calvin
Cycle uses more ATP per mole than NADPH per mole,
and hence replenishes the used ATP.
7
2. Dark Reaction/Calvin Cycle/Light Independent Reaction—
“process in which NADPH and ATP are used to make organic
compounds such as glucose.”
i. Uses the products of the light reaction (ATP and NADPH)
to produce glucose.
ii. Takes place in the stroma of the chloroplast.
Carbon Fixation Reduction
0, isfxed to ribulose ‘ATP and NADPH are
biphosphate(RuB?) used to produce
via tubisco to form alycetaldehyde
3-phosphoglycerate. 3-phosphate (63)
Regeneration
uBPis remade
5556
Chapter 12
C. Comparison Chart
Process
Breakdown of
glucose
synthesis of
glucose
O, is released
O, is consumed
Chemiosmosis
co,
is released
CO, is consumed/
fixed
ATP is produced
ATP is consumed
Pyruvate as
intermediate
NADH produced
NADPH produced
Takes Place in
Cellular Respiration
Yes
No
No
Yes—ETC and
Oxidative
Phosphorylation
Yes—ETC
Yes—Shuttle Step and
Krebs Cycle
No
Yes—Glycolysis,
Krebs Cycle, ETC
and Oxidative
Phosphorylation
Yes—Glycolysis initial
investment
Yes—Glycolysis
Yes—Glycolysis, shuttle
step, Krebs cycle
No
Takes Place in
Photosynthesis
No
Yes—Calvin Cycle
Yes—light-
dependent
reaction
No
Yes—ETC
No
Yes—Calvin Cycle
Yes—light-
dependent
reaction
Yes—Calvin Cycle
No
No
Yes—light-
dependent
reactionPhotosynthesis
D, Alternatives to Photosynthesis
1. Photorespiration
i.
i
ra
C, plants make up roughly 90% of the plants on earth
and fix carbon into a 3-phosphoglycerate (3 carbon
compound).
|. Normal photosynthetic processes take place within C,
plants.
i. When the day is hot and/or dry, stomata are closed;
therefore, less carbon dioxide enters the cell for the Dark
Reaction. Rubisco will fix oxygen rather than carbon
dioxide through a process called photorespiration.
Photorespiration will produce no ATP and the Dark
Reaction will not fix carbon, thus decreasing glucose
output.
Plants
Plants that prefer an alternative mode of carbon fixation
that forms a four-carbon compound first rather than a
three-carbon compound.
. Leaf anatomy is the main reason why C, plants have
alternative carbon fixation.
Bundle-sheath cells are found around the vein of the leaf,
and the mesophyll cells are found between the bundle-
sheath cells and the leaf surface.
@ Fixed to 4 carbon Mesophyll
Decarboxylation and Calvin Cycle Bundle-sheath
57Chapter 12
58
iv. C, plants minimize photorespiration because the enzyme
Rubisco is not as available to fix oxygen. A secondary
enzyme called PEP carboxylase fixes the carbon dioxide to
a four-carbon compound and has no affinity for oxygen.
C, plants fix carbon dioxide more efficiently than C,
plants.
. Crassulacean Acid Metabolism (CAM) Plants
i. Based on arid conditions and plants that are succulent
(water-storing).
ii, At night, CAM plants open their stomata and during the
day close their stomata.
iii, Closing the stomata during the day halts the drying out of
the plant, but also prevents carbon dioxide from entering.
iv. Opening the stomata during the night allows the plant to
take in carbon dioxide where it will be stored in the form
of organic acids.
Molecules and Cells—Some similarities between cellular
respiration and photosynthesis are always tested on the AP
Biology exam. Included are the following: ATP production,
electron transport use, compartmentalization between
chloroplast and mitochondria, hydrogen and electron
acceptor molecules, such as NADH, FADH,, and NADPH.———PART III:
HEREDITY AND EVOLUTION:
Heredity, Molecular Genetics,
and Evolutionary Biology2nediploid
ell
Meiosis and
Gametogenesis
Heredity—Meiosis and Gametogenesis
A. Genetic Terms
1, Genes—heredity units made up of DNA.
2. Locus—a gene’s specific location on the chromosome.
3. Asexual Reproduction—a form of reproduction not requiring
meiosis or fertilization. Only passes a copy of genes to
its progeny. A type of reproduction in which there is no
variation in genetic make-up. Bacteria reproduce via asexual
reproduction.
4. Clone—an individual that arises from asexual reproduction.
5. Sexual Reproduction—a type of reproduction that involves
variation because two parents give rise to their progeny.
Major evolutionary advantage because of genetic variation.
6. Somatic Cell—a body cell that is diploid.
7. Gamete—a sex cell such as egg or sperm.
Life cles of Animats and Plants
n-haploid
cell sperm
oregg
Fertilization
JaydeydChapter 13
62
B. Meiosis—Key Points
1
2.
Meiosis, like mitosis, is preceded by replication of
chromosomes.
Unlike mitosis, meiosis has two consecutive cell divisions
called Meiosis | and II.
. Division results in four daughter cells that are genetically
different and are haploid.
. Tetrads are formed or the pairing of homologous
chromosomes via synapsis. Chiasmata or the site of crossing
over/exchange of genetic material is formed in Prophase | of
Meiosis |.
._ In Metaphase | of Meiosis | homologous chromosomes pair
with each other at the metaphase plate.
. Homologous chromosomes separate in Anaphase | of Meiosis
| and sister chromatids stay together.
. Meiosis Il has no further chromosomal replications and looks
just like Mitosis.
. Chromosomes will independently assort from each other
producing variations.
. Crossing over in Prophase | is another mechanism for
variation from meiosis.Meiosis and Gametogenesis
C. Comparison of Mitosis and Meiosis
Event
DNA Replication
Homologous
Chromosomes
Sister Chromatid
Separation
Divisions
Cells Produced
Crossing Over
Mitosis
Occurs during
interphase
Align one after
another on
metaphase plate
Anaphase
1
2 Diploid—
genetically
identical
Does not occur
Meiosis
Occurs during
interphase
Pair with each other
during metaphase |.
Align one after another
on metaphase plate
during metaphase II
Meiosis II Anaphase II
2
4 Haploid—genetically
different
Meiosis | Prophase |
Molecules and Cells—Every AP Biology test-taker should
know the main differences between meiosis and mitosis.
Mitosis produces diploid identical cells that have no genetic
variation. Meiosis produces gametes (haploid) that are
genetically different because of crossing over in Prophase | of
meiosis. Similarly, know the stages of mitosis and meiosis and
special structures that are formed.
63Eukaryotic Chromosomes
Heredity—Eukaryotic Chromosomes
A. Structure and Function of Eukaryotic Chromosome
Part
Genes
Chromatids
Centromere
Chromatin
Kinetochore
Nucleosomes
Telomeres
Structure
Made up of the
nucleic acid DNA
Two replicated
chromosomes that
are held together at
the centromere
DNA region found
near the middle (not
always) chromosome
DNA and protein
combination
Proteins
Histone proteins and
DNA
Ends of DNA
Remember: Eukaryotic DNA is linear, meaning it has definite ends.
Most eukaryotic organisms are diploid. Fungi, such as yeast, can
exist as haploid or diploid.
Function
Will be transcribed
onto mRNA
Will be translated for
proteins
Allows proper
segregation of
chromosome during
meiosis and mitosis
Hold chromatids together
to form a chromosome.
Aids in packaging DNA,
DNA replication, and
expression of proteins
Allows for the attachment
of the mitotic spindle to
the centromere
Aids in packaging of DNA
Protection against the
destruction of the DNA
from nucleases
65
JaydeydChapter 14
66
B. Advantages to Chromosomes
1. Genetic variation—crossing over, independent assortment.
2. Gene regulation
3. Allows for a large number of genes to be expressed.
4.
. Diploid—allows one to have two copies of genes as a backup
mechanism.
5. Linkage of genes to be inherited together.
. Structure and Function of Prokaryotic Chromosome as a
Comparison
1. Circular in shape and much smaller than eukaryotic
chromosome.
2. Genes are arranged in operons—one promoter controlling
many genes.
. Transcription and translation are coupled processes.
. Plasmids are prevalent—extra chromosomal pieces of DNA
that carry antibiotic resistance. They are not part of the
chromosome. Autonomously replicating.
5. One origin of replication.
6. No histone proteins to condense, but DNA is supercoiled.
RwInheritance Patterns
Heredity—Inheritance Patterns
A. Inheritance Terms
1.
2.
ONAWSD
Characteristic—a heritable feature such as hair color
(phenotype).
Trait—a variant of a characteristic. Example: red or blond hair
color.
. Allele—alternative form of a gene, such as tall (7) plants are
dominant to short plants (t).
. Dominant allele—the allele that is fully expressed.
. Recessive allele—the allele that is not expressed.
. Genotype—the genetic makeup of an organism.
. Phenotype—organism’s appearance.
. Gregor Mendel—father of genetics who worked on genetic
crosses of pea plants.
. Law of Segregation—separation of alleles into gametes.
B. Genetic Crosses
1.
Monohybrid cross—a cross that tracks the inheritance pattern
of a single character.
Example: In pea plants, tall (7) plants are dominant to short
plants (t). There are three allelic combinations:
» TT—homozygous dominant (considered true breeding)/Tall
» Tt—heterozygous or hybrid/Tall
» tt—homozygous recessive (considered true breeding)/Short
67
JaydeydChapter 15
Cross two true breeding plants of tall and short
P (parental) Punnett Square
Generation-true TT x tt
breeding parents Tt Tt
tall and short ee
Tt Tt
F; (fist) Tex Tt
Generation- Punnett Square
hybrids
> IT It
F, (second filial) TT, Tt, Tt, tt Tt tt
Generation- — |-_——p>
3:1 ti
ee 3:1 tall to short phenotypically
2. Test cross—A cross that determines whether the dominant
parent is homozygous dominant or heterozygous. Always
cross the dominant parent to a homozygous recessive.
Assume black (B) is dominant to white (b) for cat coat color.
x
Black parent could be BB or Bb. White parent is bb.
> If BB x bb, all progeny will be black carriers.
> If Bb x bb, 2 of the progeny are black and ¥% are white.
~
68Inheritance Patterns
3.
. Law of Independent Assortment—is observed with dihybrid
crosses or crosses between two different characters. Alleles
assort independently from each other; therefore, dominant
can combine with recessive.
Example: In pea plants, tall (T) plants are dominant to short
plants (t). Green leaf (G) is dominant to yellow leaf (g).
Cross two true breeding plants of tall green and short yellow
P (parental) TIGG x ttgg
Generation-true Gametes Produced
breeding parents
talland short a TG and tg
Punnett Square
F; (fist fila)
Gaepnin
a Tt6g TTGG | TTGg | TTGg | TTgg
166 | Ttgg | Tt6G | TtGg
TtGg | TtGg | TtGg | Ttgg
F, (second filial)
Generation. =) L_____ ttGG | ttGg | ttGg | ttgg
9:3:3:1 ratio
9 tall, green: 3 tall, yellow
3 short, green: 1 short, yellow
C. Using the Laws of Probability in Genetics
le
The law of multiplication—independent events are governed
by this; therefore, for genes that are linked the law of
multiplication cannot be followed.
i, Assume the following cross: AaBbCc x AabbCC. What are
the chances of the following progeny?
a) AabbCC
b) aabbCc
©) AAbbCC
Answer: Perform each individual monohybrid cross and
use the law of multiplication.
Aa x Aa = 1/2 Aa, 1/4 aa, 1/4 AA
Bb x bb = 1/2 Bb, 1/2 bb
Cc x CC = 1/2 Cc, 1/2 CC
69Chapter 15
a) AabbCC = 1/2 x 1/2 x 1/2
b) aabbCc = 1/4 x 1/2 x 1/2
c) AAbbCC = 1/4 x 1/2 x 1/2 = 1/16
i, Assume the following genotype: AaBBCcddEeFf. How many
different gametes are possible?
Answer: Determine how many different gametes are
possible for each set of alleles.
Aa = 2 (either A or a)
(only B)
(either C orc) | 2x1x2x1x2x2=
(only d) 16 different gametes
(either E or e)
Ff =2 (either F or f)
D. Non-Mendelian Genetics—genetics that do not follow the
inheritance patterns of Mendel’s initial pea plant experiments.
1. Incomplete dominance—the phenotype of the offspring has
an appearance that is between that of both parents. This is
not a blending hypothesis. The dominant allele is not fully
expressed.
Snapdragons
P (parental) it Punnett Square
(era ie | Red (CC) x White (cc) al
breeding parents Cc Cc
red and white =
ie Cc
F, (first filial)
Geneation-
tybrdsal pink a naad
‘unnett square
i»
cc Cc
Cc cc
F, (second filial)
Generation- —- |__________
12:1 ratio 1:2:1 red to pink to white
70Inheritance Patterns
2. Codominance—both alleles are expressed at the same time.
> MN Blood system (M and N are blood group antigens
found on the cell surface of a red blood cell).
» There are three allelic combinations:
* MM—homozygous dominant (only produce M antigen
on cell surface).
* MN—heterozygous (produce M and N antigens on cell
surface).
* NN—homozygous recessive (only produce N antigen
on cell surface).
3. Multiple Alleles—many different alleles can control the
expression of a character.
i. ABO Blood System—carbohydrate antigens found on the
cell surface.
Antigen on
Cell Surface | Antibodies
Geno- of Red Present in
type Phenotype Blood Cell Blood
ii O blood type None Anti A, Anti B
For | Ablood type B Anti A
an
Por i) B blood type A Anti B
te AB blood type AB None
Example ABO Cross: Assume that a child has type B
blood and the father was type A. What are the possible
genotypes of the mother?
Answer: Child could be /* /’ or /* i and the father had to
be i, The mother could be either /* Por /° i or * F, If the
father was 4 no matter what genotype the mother is, a
type B child could not be produced.
4. Pleiotropy—one gene causes multiple different phenotypic
effects on an organism.
Human Disease PKU (phenylketouria) Phenotypes
Mental Retardation Hair Loss Skin Pigmentation
71Chapter 15
72
5. Epistasis—one gene affecting the expression of another gene.
F, offspring phenotypic ratio is usually 9:3:4.
Polygenic inheritance—two or more genes affecting one
phenotype. Examples include skin color and cancer, which
is the most common polygenic inherited disorder. Polygenic
inheritance leads to a bell curve distribution of phenotypes.
E. Pedigree Analysis—a visual depiction of inheritance patterns in
multiple family generations.
ne
Basic Rules
i. If two affected people have an unaffected child, it must
be a dominant pedigree: [A] is the dominant mutant
allele and [a] is the recessive allele. Both parents are Aa
(hybrid carriers) and the unaffected child is aa.
ii. If two unaffected people have an affected child, it is a
recessive pedigree: [A] is the dominant allele and [a] is
the recessive allele. Both parents are Aa (hybrid carriers)
and the affected child is aa.
iii, If every affected person has an affected parent, it is a
dominant pedigree (no skipping of generations).
iv. Dominant traits never skip generations, while recessive
traits can skip.
v. Squares are male,
vi. Circles are females. O
vii. Mating is indicated by the connection with a line.
—
viii, Filled-in circles or squares indicate affected person.
ix. Sex-linked dominant—all females descending from the
affected males have the disease.
x. Sex-linked recessive—no male carriers possible and skips
generations.
xi. Autosomal recessive—carriers are present, so skips
generations. 50% males and females affected.Inheritance Patterns
xii, Autosomal dominant—no carriers or skipping of
generations. 50% males and females affected.
F. Autosomal Genetic Disorders
Recessive Inherited Disorder—absence or
malfunction of protein
Must receive both non-functional copies from parents;
therefore, affected individual is homozygous recessive (aa).
Disease
Albinism
Cystic Fibrosis
Tay-Sachs
Sickle cell disease
Outcome
Lack of pigment in the skin, eyes, and
hair. May lead to skin cancers.
Defective or absent chloride channel
protein in membranes, causing a build-
up of mucus in lungs. Person is prone to
bacterial infections.
Defective or absent lipase enzyme in
brain. Predominant in Jewish population.
Defective hemoglobin protein. Mostly
affects the African-American population.
Dominant Inherited Disorder—absence or
malfunction of protein
Must receive at least one non-functional copy from one
parent; therefore, affected individual is heterozygous (Aa)
or homozygous dominant (AA).
Disease
Achondroplasia
Huntington’s
Disease
Outcome
Dwarfism
Degenerative breakdown of the nervous
system.
G. Linked Genes
1. Thomas Hunt Morgan performed genetic crosses with the
fruit fly (Drosophila melanogaster)
73Chapter 15
2. Terms used in fruit fly crosses.
i. Wild Type—most common phenotype in the population.
ii. Mutants—alternative phenotypes to the wild type.
3. Morgan performed the following dihybrid mating:
> Example: In fruit flies, gray (g*) body color is dominant to
black body color (g). Normal wings (w*) are dominant to
dumpy wings (w).
» Cross a double heterozygote to a double recessive (g*g
w'w x ggww).
» Expected phenotypes of 1000 offspring would be:
250 wild type (gray normal)/parental phenotype
250 black dumpy/parental phenotype
250 gray dumpy/recombinant phenotype
250 black normal/recombinant phenotype
» Observed phenotypes of 1000 offspring were:
450 wild type (gray normal) /parental phenotype
450 black dumpy/parental phenotype
50 gray dumpy/recombinant phenotype
50 black normal/recombinant phenotype
The high number of observed parental phenotypes indicated
that the genes for body color and wings were linked to each
other. Linked genes are on the same chromosome and are
very close to each other. Linked genes are inherited together
and recombination between the genes is very low.
» Calculation of Recombination Frequency or the measure of
genetic linkage between 2 genes (also called map units).
Recombination Frequency = eotirecomblnants x 100
total offspring
Using the data above:
Recombination Frequency = a x 100 = 10%
1000
Only 10% of the time will there be recombination
between the genes for body type and wings.
4. Genetic Maps
i, Recombination Frequency allows you to create genetic
maps that estimate the distance between genes.
74Inheritance Patterns
Assume the following Recombination Frequencies.
Determine the genetic map for genes W,X,Y, Z
W-Y, 7 map units
W-X, 26 map units
W-Z, 24 map units
Y-X, 19 map units
Y-Z, 31 map units
Answer: X ---
5. Sex-linked genes
Genes that are carried on the X-chromosome.
Females carry two X chromosomes, XX.
iii, Males carry 1X and 1Y, XY.
iv. Inheritance patterns of sex-linked genes:
1. A father will always transmit the sex-linked trait to his
daughter. His son receives the Y, and does not inherit
the trait.
2. Only females can be carriers of sex-linked traits.
Therefore, a carrier female who mates with a normal
male transmits the mutant allele to half her sons and
half her daughters.
3. Examples of sex-linked traits include hemophilia and
muscular dystrophy.
Barr body—one of the female’s X chromosomes is
randomly inactivated in order to have the same gene
dosage as males for sex chromosomes. The chromosome
tends to look smaller in physical structure. Example of the
phenotypic output of X-inactivation are Calico-colored cats.
6. Chromosomal Mutations
Non-disjunction of chromosomes
1. If non-disjunction takes place in Meiosis |, all 4 cells will
be aneuploid, or have abnormal chromosome numbers.
2 cells will be monosomic (n-1) and 2 cells will be
trisomic (n+1).
2. If non-disjunction takes place in Meiosis II, 2 cells will
be normal (n), 1 cell (n-1) monosomic, and 1 cell
trisomic (n+1).
75Chapter 15
76
vi.
vii.
viii.
Polyploidy—having more than two chromosome sets
such as triploid (3N).
Deletion—entire fragment of chromosome is lost.
Duplication—entire fragment of chromosome is
duplicated on the chromosome.
Inversion—part of the chromosome reverses its
orientation.
Translocation—one part of a chromosome is attached to
another part of a different chromosome.
Down Syndrome or Trisomy 21—presence of all or part of
an extra chromosome 21.
XXY—Klinefelter syndrome. Phenotypically male, but are
sterile and have reduced testes size and enlarged breasts.
XO—Turner syndrome. Phenotypically female, but have a
lack of development of secondary female characteristics.
Fragile X—abnormal X chromosome, which causes
mental retardation and autism.
Heredity and Evolution—You may have to perform simple
Mendelian crosses that are either monohydrid or dihydrid.
This may require you to work backwards from data to find the
genotypes of parents.RNA and DNA Structure
and Function
Molecular Genetics—RNA and DNA Structure
and Function
A. Deoxyribonucleic Acid (DNA)—Genetic material
B. Ribonucleic Acid (RNA)
1.
2.
3 types: mRNA (messenger RNA), rRNA (ribosomal RNA),
tRNA (transfer RNA)
All 3 are involved in the expression of genes into proteins.
C. Nucleotides
1.
Nucleic acids are made of nucleotides. A nucleotide is
composed of a 5 carbon sugar, a nitrogenous base, and a
phosphate group.
.. Two types of nitrogenous bases: purines (6-member ring
fused to a 5-member ring) and pyrimidines (6-member ring).
Purines Pyrimidines
Adenine Thymine (not found in RNA)
Guanine Cytosine
Uracil (only found in RNA)
. Two types of sugars: deoxyribose for DNA and ribose for
RNA.
|. Phosphate group (see chapter on Molecules and Cells).
. Nucleoside is a nitrogenous base and sugar without the
phosphate.
77
JaydeydChapter 16
78
Discovery of DNA as the Genetic Material
A. Transformation Experiments of Griffith, Avery, McCarty,
MacLeod.
1. Smooth (contains capsule) living Streptococcus pneumonia
injected into live mouse, resulted in a dead mouse.
2. Rough (no capsule) living Streptococcus pneumonia injected
into live mouse, resulted in a healthy mouse.
3. Heat-killed smooth (capsule destroyed) Streptococcus
pneumonia injected into live mouse, resulted in a healthy
mouse.
4. Heat-killed smooth (contains capsule) mixed with living
rough (no capsule) Streptococcus pneumonia injected into live
mouse, resulted in a dead mouse.
5. Interpretation of the experiment was that the DNA from the
heat-killed smooth cells “transformed” the rough cells into
smooth cells that killed the mouse. Transforming agent was
DNA.
. Hershey-Chase Experiment
1. Worked with T2 bacteriophage or a virus that infects
bacteria.
2. Bacteriophage were radioactively labeled with P32 (DNA) or
$35 (protein coat of bacteriophage).
3. When separate experiments were completed, it was found
that bacteria contain the radioactively labeled P32 DNA of
the bacteriophage.
4. Interpretation of the experiment was that the bacteriophage
injected their DNA into the host bacterium in order to
produce progeny phage, indicating DNA as the genetic
material.RNA and DNA Structure and Function
C. Watson and Crick
le
2.
DNA ase pair
Suga phosphat
backbone
James Watson and Francis Crick used X-ray crystallography
experiments to show that DNA is a double helix.
Data of the experiment also indicated that the double helix
had a sugar phosphate backbone with nitrogenous bases
pairing interior to the double helix.
. Base pairing rules of purines and pyrimidines were established
(also known as Chargaff’s rule).
i, Adenine (purine) pairs with thymine (pyrimidine).
2 hydrogen bonds for base pairing.
ii, Guanine (purine) pairs with cytosine (pyrimidine).
3 hydrogen bonds for base pairing.
Hydrogen bonds indicated by dashed lines.
N a
oor
MHN oF Ni
‘Adenine Thymine
Q----------- 22 == - Ni
NH-~----->7 >>> wa
< 3
NHN Wnt --- === A NH
Guanine Gtosine
79Chapter 16
D. Meselson-Stahl
1. Experiment indicated that replication of DNA is semi-
conservative, or one old strand is used for the synthesis
(template) of a new strand.
2. Experiment showed that both heavy and light nitrogen
would be incorporated into the daughter DNA during
the first round of DNA replication. In the second round
of replication, daughter strands would only have light
nitrogen since the heavy nitrogen was removed. Banding
patterns indicated a semi-conservative model is favored over
conservative or dispersive.
\ Heredity and Evolution—Every AP Biology test-taker should
Te lay know the main differences between DNA and RNA. DNA
est BARS consists of A, T, C, G as nitrogenous bases, deoxyribose as 5
Tip carbon sugar, and phosphate. RNA consists of A, U, G, C as
nitrogenous bases, ribose as 5 carbon sugar, and phosphate.
Structurally DNA is a double-stranded helix, while RNA is
single-stranded.
DNA Replication
1. Where does DNA replication begin?
i. Origins of replication (Ori) or specific DNA sequences
where replication will commence. In prokaryotes there
is one origin for replication while in eukaryotes there are
thousands of origins for replication.
ii. DNA replication proceeds in both directions on the strand,
forming what is called a replication fork.
2. Elongation
i. Elongation at the replication fork is catalyzed by an
enzyme called DNA polymerase.
3p eating sand
7
v4 3° Lagging strand
.
DNA PolymeraseRNA and DNA Structure and Function
. Nucleotides are the substrate for DNA polymerase and
ATP is hydrolyzed by the enzyme.
Strands have to be primed by an enzyme called RNA
primase. This enzyme adds a small strand of RNA for
DNA polymerase to hook to and begin the synthesis of
anew DNA strand. The RNA primer is removed later in
replication and filled in with DNA.
iv. The two strands of DNA are anti-parallel or 5’ phosphate
to 3’ hydroxyl in one direction and at the opposite end is
3’ hydroxyl to 5’ phosphate.
v. DNA polymerase only elongates the strand from 5’ to 3’.
-
5 phosphate me
3 hydroxyl 5
5; phosphate
vi. Leading Strand—the daughter strand that is synthesized
into the replication fork. This strand is synthesized in a
continuous fashion.
Lagging Strand—the daughter strand that is synthesized
away from the replication fork. This strand is synthesized
in a discontinuous fashion or in fragments called Okazaki
fragments.
viii. DNA ligase is the enzyme that will take a 5’ phosphate
and 3’ hydroxyl and link them together, helping join the
Okazaki fragments into a single strand.
vii.
81Chapter 16
82
Major Enzymes and Proteins in DNA Replication
Enzyme
DNA helicase
Single-stranded
binding proteins
DNA primase
DNA polymerase
DNA ligase
Substrate
Double-
stranded DNA
Single-
stranded DNA
Single-
stranded DNA
Single-
stranded DNA
Single-
stranded DNA
Action
Opens up the DNA strand
for replication
Binds single-stranded
DNA and keeps
replication fork open
Lays down a RNA primer
on single-stranded DNA
for DNA polymerase to
hook up with
Adds the complementary
base to the daughter
strand using the parental
template. Follows base
pairing rules; adenine
with thymine, guanine
with cytosine
Links a 5’ phosphate
with a 3’ hydroxyl on the
lagging strandGene Regulation
Molecular Genetics—Gene Regulation
A. One Gene-One Enzyme Hypothesis of Beadle and Tatum
1.
2.
Used auxotrophs (nutritional mutants) of Neurospora crassa.
Wild type can grow on a minimal media while several other
class mutants were not able to grow on minimal media
unless supplemented.
. Each mutant had a specific metabolic deficiency because the
gene that produced the required enzyme was mutated.
B. Transcription
1.
Synthesis of single-stranded mRNA (messenger RNA) from
DNA.
2. Nuclear event.
. Major enzyme involved is RNA polymerase, and runs in a
5’ to 3’ direction.
. RNA polymerase binds to a promoter or sequence in the
DNA that allows for the initiation of transcription. Part of the
promoter has a sequence of 5’TATAAA3’ called TATA box.
. Eukaryotic cell transcription factors along with RNA
polymerase promote transcription.
.. Complementary base pair in RNA is different from that found
in DNA. The base pairing is adenine with uracil and guanine
with cytosine.
. Termination of transcription requires a sequence in the DNA
called the terminator.
83
JaydeydChapter 17
8. mRNA in eukaryotes is modified after it is synthesized from
RNA polymerase. A poly A tail and 5’ 7-methylguanosine cap
are added to aid in the stability of the message.
9. RNA splicing is a process in which nonprotein coding
portions of pre-mRNA called introns are excised, while
coding portions called exons are spliced together to form a
fully functional mRNA molecule. Protein complex called the
Spliceosome catalyzes this cut-and-paste mechanism.
C. Translation
1. Synthesis of protein from mRNA in the 5’ to 3’ direction.
2. Takes place in the cytoplasm and the rough ER.
3. Requires all 3 RNA molecules (mRNA, tRNA, and rRNA) and
codons (sets of 3 nucleotide RNA bases that code for amino
acids).
4, As mRNA threads itself through the ribosome, initiation of the
process begins with a location of the start codon AUG (calls
for the amino acid methionine).
5. Once the start codon is found, a t-RNA molecule containing
the appropriate amino acid is brought to the ribosome.
The tRNA molecule binds to the codon via an anticodon
complementary sequence which is located on tRNA. Once
the binding happens, the entire ribosome translocates down
another 3 bases and reads another codon sequence, where
another tRNA brings in the appropriate amino acid. A peptide
bond between amino acids is formed via an enzymatic
reaction promoted by the rRNA portion of the ribosome.
6. Termination of translation happens when one of the
following codons is read: UAA, UGA, UAG.
84Molecular Genetics—Mutation
Mutation
A. Mutation—changes in the genetic material.
1. Two types of point mutations: Base pair substitution and base
pair insertions or deletions.
2. Mutagens—Physical or chemical agents that promote
mutations. Examples include UV light, X-rays, and chemicals
such as bromine or chlorine.
Name of Mutation
Base Pair
Substitution
Silent Mutation
Base Pair
Substitution
Missense Mutation
Example
Wild Type mRNA
AUG-CCU-UAC
Protein MET-PRO-TYR
Mutant mRNA
AUG-CCG-UAC
Protein MET-PRO-TYR
Wild Type mRNA
AUG-CCU-UAC
Protein MET-PRO-TYR
Mutant mRNA
AUG-CCU-UGC
Protein MET-PRO-CYS
Consequence
No change in protein
sequence because
the genetic code is
redundant.
Change in protein
sequence because
the UGC calls for a
different amino acid.
Most likely will change
the structure, thus the
function of protein.
(continued)
85
JaydeydChapter 18
Name of Mutation
Base Pair
Substitution
Nonsense Mutation
Insertion or Deletion
Single Base Pair
Insertion or Deletion
Three Base Pair
Example
Wild Type mRNA
AUG-CCU-UAC
Protein MET-PRO-TYR.
Mutant mRNA
AUG-CCU-UAA
Protein MET-PRO-STOP
Wild Type mRNA
AUG-CCU-UAC
Protein MET-PRO-TYR
Mutant mRNA
AUG-CCA-UUA-C
Protein MET-PRO-LEU
Wild Type mRNA
AUG-CCU-UAC
Protein MET-PRO-TYR
Mutant mRNA
AUG-CCU-UAC-UUU
Protein MET-PRO-TYR-
PHE
Consequence
Premature stop codon
put into protein. Protein
is usually nonfunctional.
Change in protein
sequence because of the
shifting of the sequence
by the addition of a
base. Similarly can
happen if one base
is deleted. Protein is
usually nonfunctional.
Addition or loss of
amino acid due to
insertion or deletion
of 3 bases. Protein will
most likely retain some
normal function.
86Viral Structure and
Replication, Bacterial
Gene Regulation
Viral Structure and Replication,
Bacterial Gene Regulation
A. Genome
Various types of genomes including the following: double-
stranded DNA, single-stranded DNA, double-stranded RNA,
or single-stranded RNA.
B. Capsids and Envelopes
1.
2.
Protein coat that protects the viral genome is called a capsid.
Viral envelopes—extra protection layer that surrounds the
capsid.
C. Viral Reproduction
1.
Host cells—the virus will invade and eventually live off of
the host by taking over the metabolic machinery (parasitic).
Viruses cannot reproduce independently.
. Interferon—class of drugs produced by cells in response to
viral infection.
. Virus attaches to the host via cell surface receptors and injects
its DNA.
.. Lytic Cycle—type of viral reproduction that eventually kills the
host.
. Lysogenic Cycle—virus will replicate its genome, but does not
kill the host. Formation of prophage, or incorporation of the
viral DNA into the host chromosome.
87
JaydeydChapter 19
88
. Human Immunodeficiency Virus or HIV, the causative agent of
Acquired Immune Deficiency Syndrome (AIDS)
1. Retrovirus—RNA virus that uses an enzyme called reverse
transcriptase to synthesize DNA from an RNA strand.
2. Infects T4 helper cells.
. Prion—protein infectious particle or misfolded protein that
converts other normal proteins into a mutant form. Causative
agent for “mad cow disease.”
Bacterial Gene Regulation
A. Plasmid—autonomous piece of self-replicating DNA.
B. Genetic Recombination in Bacteria
1. Transformation—bacteria uptaking DNA from an outside
source. This is the crux of the Griffith, Avery, McCarty,
MacLeod experiment outlined in Chapter 16.
2. Transduction—bacteriophages acting as vectors by moving
bacterial genes from one bacterial cell and transferring to
another.
3. Conjugation—formation of sex pilus between two bacteria
that allows them to share genes with each other.
4. Transposons—transposable genetic elements or jumping
genes. Genes being moved from one location to another in
the cell’s genome.
C. The Lactose Operon
1. Operon—sets of genes under the control of promoter.
2. Lactose Operon—operon required for the utilization of lactose
as a carbon source.
i. Structural genes—lacZ, lacY, lacA
ii, Regulatory genes—lacl (repressor)
3. All bacterial gene regulation is done through the interaction
of repressor proteins with specific DNA sequences called
operators (found in the promoter region of a gene).Viral Structure and Replication, Bacterial Gene Regulation
4. Repressor proteins bind to the operator sequence, acting
as a blockade to stop RNA polymerase from binding to the
promoter.
5. When the inducer is present, it will bind to the repressor,
causing it to fall off the operator allowing RNA polymerase
to transcribe the structural genes of the pathway.
6. The interplay of the inducer and repressor is the “hallmark”
of bacterial gene regulation.
Repressor bound to operator
Operon in off position; no lactose present
tact Promoter Operator lock lacy lack
|
Repressor
RNA
Polymerase
Repressor not bound to operator
‘Operon in on position; lactose present
fac\ Promoter Operator | lacZ | foc | tack
RNA oe
Polymerase
wow
Gene | Product Action
lacl Repressor Shuts operon off
lacZ Beta-galactosidase | Breaks down lactose
lacY Permease Allows lactose in cell
lacA Transacetylase Modifies lactose breakdown
Heredity and Evolution—The classic example of gene
expression is the Lactose Operon. It is a good example to
compare and contrast with eukaryotic gene expression in
essays.
|s9Nucleic Acid Technology
and Applications
DNA Cloning
1. Restriction Enzymes—enyzmes that cut DNA at particular
sequences called restriction sites.
Example: Restriction site
ACTGGA— ed A CIGGA—
————
—Toacct— Tone TF
2. Recombinant DNA—combining DNA sequences that would
not normally occur together to form one piece of DNA. The
enzyme DNA ligase is added to seal the strands together.
CIGGA~
TGACC be
A GG >
GACC - DNALigase
ut DNA Foreign DNA Recombinant DNA
3. Cloning Vector—original plasmid that is used to carry foreign
DNA into a cell and replicate there.
fsa
DNA with ONA
cue) = | a igen
lacZ genes restriction site. fu
foreign DNA
[seme
Into bacterial hast,
eS
Plate on media
containing ¥-gal
and ampcilin as
Bacterial cone thats white and grows on plates clone containing recombinant DNA plasmid
(See explanation on next page.)
91
JaydeydChapter 20
92
. When the restriction enzyme is added to plasmid, lac Z is
destroyed and non-functional. The fac Z gene produces
the enzyme -galactosidase, which breaks down the
sugar X-gal causing the colony to appear blue. If the /ac
Z gene product is not made, the colony appears white; if
the gene is functional the colony appears blue.
. Ampicillin resistance gene allows bacteria to grow in the
presence of the antibiotic ampicillin.
. Media is selective for clones that have the ampicillin
resistance gene, and differential for blue or white
colonies.
. Colony that is growing on plate (ampicillin resistance)
and white are correct clones carrying recombinant DNA.
DNA Gel Electrophoresis
Ne
2.
w
DNA is placed in gel made of a polysaccharide called agarose
or acrylamide (used for smaller fragments).
Migration of DNA is based on size differential of DNA
fragments. An electric field is passed through DNA molecules
and the molecules will travel toward the positive end
(cathode) due to negative charge of phosphate on DNA.
. Larger molecules travel slower, smaller molecules travel faster.
4. Marker DNA of a standard size is used to approximate the
size of unknown molecules. Marker is measured in kilobase
pairs.
. Visualization of DNA is done by staining gel with ethidium
bromide, which increases the visual difference between DNA
and gel.Nucleic Acid Technology and Applications
Lane 1 lane? lane 3 lane 4
Lane 1— Marker DNA/Standard Size
Lane 2— 2 bands roughly 9 kb and 3 kb
Lane 3~ 1 band roughly 1.8kb
Lane 4— 3 bands roughly 12 kb, 7 kb, and 1 kb
Electrophoresis can be used for DNA and protein
identification, isolation of types of DNA or protein,
calculating the size of fragments (DNA and protein), crime
scene investigation, and genetic testing.
Polymerase Chain Reaction
Ub
2.
A method to take a small amount of DNA and amplify the
amount.
Based on progressive heating and cooling of DNA strands
with the addition of primers and DNA polymerase.
93Chapter 20
94
DNA Fingerprinting
1. A technique used by forensic scientists to help determine the
DNA of individuals.
2. The DNA of humans is highly homologous. There are
sequences called Short Tandem Repeats (STR). These repeats
vary in length and size for each human, and therefore, can be
used as identifying factors of humans.
3. STRs can be visualized using DNA gel electrophoresis.
Heredity and Evolution—Fully understanding the cloning
process is considered a major concept in the AP Biology
curriculum. You should understand how restriction enzymes
and vectors are used in tandem to construct a recombinant
plasmid.Early Evolution of Life
Early Evolution of Life
A. Earth and Early Life
1.
2.
Earth is most likely around 5 billion years old.
Anaerobic prokaryotes emerged approximately 4 billion years
ago and represent the first origin of life.
. Earliest living organisms were unicellular, had a genetic code,
and were able to evolve and reproduce.
. Prokaryotes diverged into two types—bacteria and archaea—
about 2.5 billion years ago.
.. Oxygen accumulated in the atmosphere approximately 2.5
million years ago as a result of photosynthetic bacteria.
. Eukaryotes emerged 2 billion years ago via the Endosymbiotic
Theory—larger prokaryotic species engulfed smaller ones
that continued to live and function within the larger host
cell. Eventually, the mitochondria and chloroplasts were the
two organelles created from these smaller cells, resulting in a
eukaryotic cell.
. Prior to 500 million years ago, life was confined to aquatic
environments. Plants eventually found a foothold on earth
(root system) via a symbiotic relationship with fungi.
B. The Early Atmosphere
1.
Primitive earth was thought to have the following
atmospheric molecules—water (H,O), methane (CH,),
hydrogen (H,), and ammonia (NH,). No oxygen.
. Miller-Urey Experiment—tested the Oparin-Haldane model
that the atmosphere on primitive earth was the precursor for
the synthesis of organic molecules.
|95
JaydeydChapter 21
96
i, The primitive atmosphere components when given
electric spark eventually formed crude organic molecules
including sugars, lipids, amino acids, and nucleic acids.
ii, Heterotrophic Hypothesis—first forms of life were
prokaryotic heterotrophs that used non-biologically
produced organic matter, via the Oparin-Haldane model,
as their carbon source. Still no oxygen produced.
C. RNA—The First Genetic Material
1. RNA was most likely a self-replicating molecule found in
aquatic environments.
2. RNA can self-catalyze its synthesis via its ribozyme (RNA
enzyme) capability.
3. Eventually, DNA became the genetic material, because of its
stability over RNA and ability to correct mutations.
D. Current Models for the Origins of Prokaryotic and Eukaryotic
Cells
3-Domain Model
Domain
Archaea
Dom:
Bacteria
Domain
Eukarya
\ Indicates Archaea
and Eukarya have
commonalities
Universal
Ancestor
1. Carl Woese developed a domain level that is more inclusive
than the Kingdom system.
2. Universal Ancestor—primordial organism that was unicellular,
anaerobic, prokaryotic, used ATP for energy and DNA as the
genetic material.
3. Bacteria and archaea are both at the prokaryotic level, but
archaea live in more harsh conditions than bacteria.4.
Early Evolution of Life
Types of Archaea
Methanogens—produce methane and are used to convert
waste to CH,.
Acidophiles—thrive under highly acidic conditions.
| Halophiles—thrive under high salt conditions.
| Thermophiles—thrive under high temperature conditions.
When comparing archaea to eukarya, they have much in
common with each other (more than bacteria). Examples
include several types of RNA polymerase, introns, ribosome
structure, RNA sequence, and non-response to antibiotics.
E. Early Prokaryotic Characteristics
io
2.
Origination—around 4 billion years ago
Anaerobic fermentation (glycolysis)\—primary metabolic
pathway
. Used organic compounds made via Oparin-Haldane Model—
Heterotrophic Hypothesis
|. Eventually chemoautotrophs were selected because of their
ability to make energy when the environment had been
depleted for ATP.
. Cyanobacteria (blue-green algae)—photosynthetic bacteria
that were able to produce oxygen.
F. Early Eukaryotic Characteristics
wRWnNo
. Earliest eukaryotic descendents of prokaryotes were Protists.
. Diverse unicellular organisms.
. Motile, having cilia and flagella.
. Can be photoautotrophs or heterotrophs.
. Endosymbiotic Theory—Larger prokaryotic species engulfed
smaller ones that continued to live and function within the
larger host cell. Eventually, the mitochondria and chloroplasts
were the two organelles created from these smaller cells,
resulting in a eukaryotic cell. Developed by Lynn Margulis.
97Chapter 21
98
Evidence for Endosymbiotic Theory
Mitochondria and chloroplasts have DNA similar to
prokaryotic DNA (sequence and shape are circular).
Mitochondria and chloroplasts are double membrane and
double bound, similar to prokaryotes.
Mitochondria and chloroplasts are similar in size to
prokaryotes.
Mitochondria and chloroplasts have their own ribosomes
like prokaryotes.
Mitochondria and chloroplasts reproduce via binary fission
like prokaryotes.
& 4 Heredity and Evolution—Being able to clearly identify the
characteristics of early prokaryotes has been a hallmark of all
AP Biology tests.Evidence for Evolution
Evidence for Evolution
A. Early Theories
1.
In the 1700s and 1800s, the biological sciences were defined
in terms of natural theology, rather than scientific data and
extrapolation. Several scientists began to use data to debunk
natural theology as a means for explaining scientific findings.
. Carolus Linnaeus—founder of taxonomy or the classification
of organisms based on anatomical similarities and differences.
Developed the binomial system or Genus species, ex. Homo
erectus.
. Georges Cuvier—developed paleontology or the study
of fossils found in sedimentary rock. Coined the term
catastrophism—strata in sedimentary rock was reflective of a
catastrophic event that took place.
. James Hutton—used the geologic concept of gradualism—
major change in geology is a slow and ongoing process.
. Charles Lyel—used the geologic concept of
uniformitarianism—that the earth was shaped entirely by
slow-moving forces still in operation today, acting over a very
long period of time
. Thomas Malthus—indicated that populations could grow so
rapidly, they could outgrow their food supplies.
. Jean Baptiste Lamarck—developed Lamarckism—traits can be
inherited from one generation to the next via the process of
“the inheritance of acquired characteristics.” For example,
a giraffe’s neck gets longer with each successive generation
or a good baseball player can pass his traits to his children.
There is no evidence, however, to prove this theory that
|99
JaydeydChapter 22
in “acquired characteristic” can be passed to the next
generation. Another name for this is use and disuse; if a trait
is used it will be passed down to the next, but, if not used, it
will be discarded and not passed along. His theory was still
considered visionary because of its emphasis on adaptation
to the environment.
B. Descent with Modification—The Darwinian World
1. English scientist Charles Darwin voyages on the HMS Beagle
to explore the South American coastline.
2. On the Galapagos Islands he found 12 different types of
finches that were similar, but each had unique characteristics.
3. Darwin made a link between the origin of a new species and
the environment in which these species reside.
4. The theory of natural selection is coined—reproductive
success of an organism depends on its ability to adapt to the
environment in which it resides. For example, several of the
finches in the Galapagos Islands adapted their beak structure
in order to find food.
5. Postulates of natural selection—
i. If the environment cannot support the individuals who
occupy it, then most of the offspring will perish.
ii, Survival of individuals within a population will depend on
the genetic background of the individual. Individuals with
the best traits will survive. Another name for this is the
“survival of the fittest.”
|. Over time, the fittest organism will survive and therefore
changes in the population will take place to benefit the
reproduction of the population.
The result of natural selection is the adaption of
populations to their environment, thus giving
them a competitive advantage to survive.
iv. Below is a classic example of natural selection
(hypothetical data). The graph indicates that as time
changes, the average beak length of a finch changes
depending on the season. During a dry season the
average beak length gets slightly larger, giving the finches
100Evidence for Evolution
a better advantage to transverse terrain and outcompete
other birds for seeds that are less abundant in a wet
season. A larger beak indicates a competitive advantage
and survival of the fittest. Dry seasons are 1950 and 1980;
wet seasons are 1960, 1970, 1990, and 2000.
eS
Beak Length (cm)
PTT
1940 ©1950-1960» «1970 «1980» 1990» 20002010
Year
C. Evidence for Evolution
le
Biogeography—study of organisms and how they relate
to the environment. Organisms may be unique to certain
geographies that are present in one particular location.
Hence, the organism has adapted to live in that environment.
. Fossils—help indicate the progression of organisms from
simple to complex. For example, transitional fossils are fossils
of animals that display a trait that helped the organism attain
a competitive advantage. At one time whales had limb-like
fossils indicating they may have been land dwellers at one
time.
. Comparative Anatomy—study of anatomical similarities
between organisms. Homologous structures—structures with
organisms that indicate a common ancestor. For example,
a human arm, cat leg, whale flipper, and bat wing all have
a similar structure, but different functions. Vestigial organs—
remnants of structures that were at one time important for
ancestral organisms.
|. Comparative Embryology—comparing the embryonic
development of one organism to another.
101Chapter 22
5. Molecular Biology—used in the study of evolution by looking
at homology in DNA and protein sequences. See chart in
Chapter 3 on cytochrome proteins. This is the best evidence
that can be used when studying the relationships of species.
Heredity and Evolutlon—Darwinian biology permeates all
aspects of biology. Knowing the evidence of evolution and
early theories of evolution can make up a series of questions
on the AP Biology exam.
102Mechanisms of Evolution
Mechanisms of Evolution
A. Population Genetics
1.
2.
Population Genetics—study of genetic variation within a
population of individuals.
Population—a group of individuals that belong to the same
species.
. Gene Pool—the total sum of genes within a population at a
given time.
. Hardy-Weinberg—study of the gene pool of a non-evolving
population.
. Hardy-Weinberg can only be met if the following five
conditions are met:
No mutation
. No gene flow or genetic variation
iii, A very large population sample
iv. No natural selection
v. Random mating
.. Mathematical Relationship of Hardy-Weinberg—equation
that can help you determine whether a population is in
Hardy-Weinberg equilibrium
i, _p =represents the frequency of the dominant allele
= represents the frequency of the recessive allele
iii, Assume a population of 500 pea plants in which green is
dominant to yellow.
103
JaydeydChapter 23
A = green, a= yellow
Phenotype Green Green
Genotype AA Aa
Number of pea 320 160
plants (total = 500)
Genotypic 320/500 = | 160/500 =
frequencies 0.64 AA 0.32 Aa
Number of alleles 320x2= 160A&
in gene pool 640A 160a
Allelic frequencies | 800/1000= | 200/1000 =
0.8A 0.2a
p = frequency | q = frequency
of A=0.8 ofa=0.2
Yellow
aa
20
20/500 =
0.04 aa
40a
>» p+q=1 (combined gene frequency must be 100%)
> p?+2pq+q?=1
* p?= frequency of AA genotype = 0.8 x 0.8 =
0.64 = 64%
* 2pq = frequency of Aa genotype = 2 x 0.8 x 0.2 =
0.32 = 32%
* q?= frequency of aa genotype = 0.2 x 0.2 = 0.04 = 4%
7. Sample AP Biology Problem Using Hardy-Weinberg (Know
this concept . . . it is always on AP tests):
Assume that in a population of insects, body color is being
studied. 36% represent the orange color which is recessive
to 64% which represent the black dominant phenotype.
each successive generation maintains
thealll frequency, the population is said
tobe in Hardy-Weinberg equilibrium.
1) Determine the allelic frequencies.
2) Determine the genotypic frequencies.
© The recessive phenotype is key to this problem because
the dominant represents both AA and Aa. However,
recessive is ONLY represented by aa. Use logic that
q’ =aa, therefore the square root of .36 or q =
Since p+ q=1, p +0.6 =1, then p = 0.4.
104
0.6.Mechanisms of Evolution
* Allelic frequencies are A = 0.4, a = 0.6.
* Genotypic frequencies follow the equation
p?+2pq+q?=1.
© p?=0.47 =0.16 = 16%
(AA or homozygous dominant) — Black phenotype
2pq=2 x 0.6 x 0.4 = 0.48 = 48%
(Aa or heterozygous) > Black phenotype
0.6? = 0.36 = 36%
(aa or homozygous recessive) > Orange phenotype
16 + 48 + 36 = 100
q
B. Microevolution
Up
Microevolution—defined as evolution on small scale from one
generation to the next.
i. Genetic Drift—changes in the gene pool due to chance
because of a small population. The small population
directly contrasts the large population needed to maintain
Hardy-Weinberg equilibrium.
|. Bottleneck Effect—changes in the gene pool due to some
type of disaster or massive hunting that inhibits a portion
of the population from reproducing. The small population
directly contrasts the large population needed to maintain
Hardy-Weinberg equilibrium.
|. Founder Effect—a new colony is formed by a few members
of a population. The smaller the sample size, the less the
genetic makeup of the population. The small population
directly contrasts with the large population needed to
maintain Hardy-Weinberg equilibrium.
iv. Gene Flow—transfer of alleles from one population
to another through migration. The gametes of fertile
offspring mix within a population, providing genetic
variation. Genetic variation directly contrasts the no-
gene-flow postulate needed to maintain Hardy-Weinberg
equilibrium.
v. Mutation—a change in the genetic makeup of an
organism at the DNA level. Mutation directly contrasts
the no mutation postulate needed to maintain Hardy-
Weinberg equilibrium.
‘i, Non-random Mating—individuals mating with those in
close vicinity. Non-random mating directly contrasts with
vi
|105Chapter 23
the random mating postulate needed to maintain Hardy-
Weinberg equilibrium.
vii. Natural Selection—reproductive success of organisms
depends on their ability to adapt to the environment in
which they reside. Natural selection directly contrasts with
the no natural selection postulate needed to maintain
Hardy-Weinberg equilibrium.
C. Modes of Natural Selection
1. Natural Selection will favor the allelic frequency in three
ways. Below is an example of a bell curve or normal
distribution population. Three types of selections can take
place that shift the bell curve to different frequencies (hence,
evolution is taking place).
Original frequency of individuals
shows a normal“bell-curve”
distribution
Frequency of
Individuals
Phenotype
Ht
Stabizing Selection —Extreme
phenotypes are removed and
more common phenotypes
are selected
Frequengy of
Individuals
Phenotype
106Mechanisms of Evolution
Directional Selection —One of
the extreme phenotypesis
selected
Frequency of
Individuals
Diversitying Selection —Both of
‘the extreme phenotypes are
selected
Frequency of
Individuals
Phenotype
D. Macroevolution
1. Macroevolution—evolution that forms new taxonomic groups.
2. Speciation—the origin of new species (a population of
individuals who can mate with each other and produce viable
offspring).
3. Barriers to Speciation (Pre-zygotic)—before the zygote is
formed.
i. Habitat Isolation—two species may live in the same area,
but have a different habitat. One may be tree dwelling,
while another may be terrestrial.
ii. Behavioral Isolation—two species may display totally
different behaviors that do not attract each other for
mating.
iii. Temporal Isolation—two species may breed at different
times of the day or different seasons.
iv. Mechanical Isolation—two different species may be
anatomically different.
107Chapter 23
v. Gametic Isolation—two different species produce gametes
that will not fuse to form a zygote.
4. Barriers to Speciation (Post-zygotic)—after the zygote is
formed.
i, Reduced Hybrid Viability—zygote is formed but the zygote
does not live.
ii, Reduced Hybrid Fertility—hybrid offspring are born and
mature, but the hybrid cannot produce viable offspring.
E. Speciation—How Does It Occur?
1. Allopatric Speciation—populations are separated by
geographical isolation, thus a new species can be formed
following adaption to new surroundings.
i. Adaptive Radiation—Evolution of a large number of species
from a common ancestor. Examples of this are the finches
Darwin found on the Galapagos Islands.
2. Sympatric Speciation—populations are not separated by
geographical isolation, but a new species is formed amongst
the parent populations.
i. Autopolyploidy—meiotic error causes a species to have
more than two sets of chromosomes. Contribution is from
one species.
ii, Allopolyploidy—polyploidy is a result of two different
species.
F. Speciation—How Fast Does It Occur?
1. Gradualism—species are produced by slow evolution of
intermediate species.
2. Punctuated Equilibrium—speciation happens quickly at first
and then is followed by small changes over a long period of
time.
Heredity and Evolutlon—Do you like math? Let's hope so
jase because there may be easy mathematical calculations on
Test sec6 % the AP Biology test. For example, you should know how to
Tip EY ~ appropriately use the Hardy-Weinberg equation: p + q = 1,
p? + 2pq + q’ = 1. Also make sure you understand how to use
the chi-square equation—don’t memorize it. If needed, it will
<7].
2
be given to you: X? = 5
108———PART IV:
ORGANISMS
AND POPULATION:
Diversity of Organisms,
Structure and Function
of Plants and Animals,
EcologyEvolutionary Patterns
Jaydeyd
Evolutionary Patterns of Animals
A. Body Plans of Animals
1.
Phylum Porifera—represent sponges. Lack true tissues and
do not have nervous, digestive, or circulatory systems. Many
Porifera are sessile or attached to some type of environment.
2. Phylum Cnidaria—represent hydra, jellyfish, and sea
anemones. These organisms have radial symmetry. Radial
symmetry indicates the organism has a top (dorsal end) and
a bottom (ventral), but no left or right. Bilateral symmetry—
organism has dorsal, ventral, anterior (head), and posterior
(tail). Phyla included are Platyhelminths (flatworms), Rotifera
(rotifers), Nematoda (nematodes), Mollusca (clams, snails),
Annelida (segmented worms), Arthropoda (crustaceans,
insects, spiders), Echinodermata (sea urchins), and Chordata
(vertebrates).
i. Cephalization—all bilateral organisms have this process
associated with them. Anterior region of organism
contains sensory paraphernalia. This will allow for the
development of the central nervous system (brain and
extending nerve cord). Bilateral organisms need to move,
crawl, burrow, or even walk, which indicates the salient
need for a CNS.
B. Germ Layers
1. Gastrulation—the process of layering the embryo into
three germ layer regions (triploblastic). Phylum Cnidaria are
diploblastic; all others are triplobastic.
111Chapter 24
112
i, Ectoderm germ layer—outer part (ecto-) of the germ layer
and produces central nervous system, the lens of the eye,
ganglia and nerves, the epidermis, hair, and mammary
glands.
ii. Endoderm germ layer—innermost part (endo-) of the germ
layer and produces the stomach, the colon, the liver, the
pancreas, the urinary bladder, the intestines, the lining of
the urethra, the epithelial parts of the trachea, the lungs,
the pharynx, the thyroid, and the parathyroid.
Mesoderm layer—middlemost part (meso-) of the germ
layer and produces skeletal muscle, the skeleton, the
dermis of the skin, connective tissue, the urogenital
system, the heart, blood, and the spleen.
C. Body Cavities
Ne
Coelom—a body cavity completely lined with mesodermic
tissue allowing the organs to grow independent of a body
wall (thus allowing regulation of one-organ system not
affecting another). Having a coelom also allows for larger
body size and cushioning and protecting internal body parts.
A coelom is a true evolutionary advantage for an organism.
i. Coelomates have a true coelom. Phyla include Mollusca,
Annelida, Arthropoda, Echinodermata, and Chordata.
|. Acoelomates completely lack a coelom. Phylum includes
Platyhelminthes.
Pseudocoelom—a body cavity that is only partially lined by
mesodermic tissue. Phyla include Rotifera and Nematoda.
D. The Coelomate Dichotomy
ls
Protostomes—coelomate phylum that includes Mollusca,
Annelida, amd Arthropoda.
i. Spiral Cleavage and Determinate Cleavage of Embryonic
Cell—causes small cells to be adjacent to larger cells at the
8-cell stage. Determinate cleavage at this point indicates
the cells at this stage form an inviable embryo if separated
from one another.Evolutionary Patterns
ii, Coelom Formation—coelom forms from splits in the
mesoderm.
iii. Blastopore (opening of archenteron or primitive gut
system)—mouth develops from blastopore
2. Deuterostome—coelomate phylum that includes
Echinodermata and Chordata.
i. Radial Cleavage and Indeterminate Cleavage of Embryonic
Cell—causes all cells to be aligned with each other at the
8-cell stage. Indeterminate cleavage at this point indicates
the cells at this stage form a viable embryo if separated
from one another.
ii, Coelom Formation—coelom forms from folds of the
archenteron.
iii, Blastopore (opening of archenteron or primitive gut
system)—anus develops from blastopore
Organisms and Population—The topic of evolutionary
patterns of animals eludes many students during studying.
This topic is worth 2-3 questions on the AP Biology test. Be
sure you know it!
113,Survey of the
Jaydeyd
Diversity of Life
Survey of the Diversity of Life
A. Representative Organisms of Domain Bacteria Kingdom Monera
1.
2.
3.
4.
Unicelluar, prokaryotic, with no nucleus.
No membrane-bound organelles
Archaea—“ancient bacteria.” See chapter 21.
Eubacteria—true bacteria.
i. Have specialized cell wall made up of peptidoglycan
(protein and sugar).
ii. Gram-negative bacteria stain pink because of complex cell
wall.
iii. Gram-positive bacteria stain purple because of less
complex cell wall.
iv. Decomposers—feed on dead or decaying organisms.
v. Nitrogen fixation
vi. Coccus—spherical shape.
vii, Bacillus—rod shape.
viii. Spirillum—spiral shape
ix. Endospore—protective layer formed by bacteria that
protects them from harsh conditions such as heat,
pressure, or lack of food.
. Common Eubacteria
i. Escherichia coli or E.coli—intestinal pathogen.
ii. Streptococcus pneumoniae—causative agent of bacterial
pneumonia.
iii. Bacillus anthracis—soil dwelling and causative agent of
anthrax.
. How Eubacteria Gain Energy
i. Photoautotroph—use photosynthesis or light energy to
make carbon sources.
|115Chapter 25
i. Chemoautotroph—need carbon dioxide for carbon source,
but inorganic molecules for energy.
Photoheterotroph—use light energy to make ATP, but need
carbon from an outside source.
iv. Chemoheterotroph—consume organic molecules for
energy and carbon.
B. Representative Organisms of Domain Eukarya Kingdom Protista
1. Most diverse of all eukaryotes.
2. Unicelluar or multicelluar.
3. Protozoans—animal-like protists.
i, Amoeba
ii, Algae
4. Unicellular algae—plant-like protists.
i. Euglena
ii. Dinoflagellates
iii, Diatoms
5. Motion classification
i. Amoeba—move by a false foot or pseudopodia.
Ciliates—move via cilia.
iii. Flagellates—move via flagella.
C. Representative Organisms of Domain Eukarya Kingdom Fungi
1. Yeast (unicellular) or multicellular.
2. Saprobes—derive their nutrition from nonliving organic
material.
3. Lichens—symbiotic relationship between fungus and
cyanobacterium.
4. Produce antibiotics that work against prokaryotic cells. The
best example of this is Penicillium chrysogenum, or fungus that
produces the antibiotic penicillin.
D. Nine Major Animal Phyla
1. Phylum Porifera
i. Sponges.
ii, Invertebrates that have a porous body, thus they are filter
feeders.
116Survey of the Diversity of Life
ii, Anchored to a stratum.
/, Radial symmetry.
. Phylum Cnidaria
i. Hydra, sea anemone, jellyfish (tentacle-containing
organisms).
ii. Invertebrates that have a true gastrovascular cavity
(mouth).
iii. Radial symmetry.
. Phylum Platyhelminthes (planaria)
i. Flatworms.
ii, Invertebrates that a have a true gastrovascular cavity
(mouth).
iii, Bilateral symmetry.
iv. Simple nervous system and first organisms to have
cephalization.
. Phylum Nemotoda
i. Nemotodes or round worms (parasitic).
ii, Invertebrates with a complete digestive tract (mouth and
anus).
iii. Bilateral symmetry.
. Phylum Annelida
i, Invertebrates.
Segmented worms such as the earthworm or leech.
iii, Bilateral symmetry.
. Phylum Mollusca (mollusks)
i. Very diverse phylum of invertebrates.
ii. Clams, snails, squid, octopi, scallops.
iii, Major parts of all mollusks
a. Visceral mass—organ-containing system
b. Head-foot region—head for sensory function, and foot
for motor function.
c. Mantle—secretes the shell.
d. Radula—sharp tongue for eating.
. Phylum Arthropoda
i. Phylum containing the most number of animals because
of insect class.
ii, Invertebrates
iii, Major parts of all arthropods.
a. They have a so-called exoskeleton or hard outer
covering that supports and protects muscles.
117Chapter 25
b. Jointed appendages.
c. Segmented body.
8. Phylum Echinodermata
i. Invertebrates that include sea stars and sea urchins.
ii, Radial symmetry.
iii. Spiny skin, an endoskeleton, and a water vascular system
for food and waste transportation.
9. Phylum Chordata
i. Most chordates are vertebrates, but not all.
ii. Major parts of all chordates.
a. Notochord that supports the back.
b. Dorsal hollow nerve cord.
c. Pharyngeal gill slits for feeding.
d. Post-anal tail.
E. Chordate Classes
1. Class Osteichthyes
i. Bony fish
ii, Gill formation for breathing
iii. Operculum—flap above gill that allows the fish to breathe
without moving.
2. Class Amphibia
i. First terrestrial vertebrates
Limb development for movement
|. Cold-blooded
iv. Lay eggs in water
v. Gills replaced by lungs
3. Class Reptilia
i. Scales for waterproofing.
ii, Terrestrial amniotic egg. There are four extra embryonic
membranes that are adaptations of the terrestrial egg:
chorion contributes to the formation of the placenta;
amnion sac cushions the embryo; yolk sac provides
nourishment for the egg; and allantois collects waste
materials and exchanges gases from the embryo.
iii. Ectothermic—warm bodies via heat from environment.
4. Class Aves
i. Wings, feather, and hollow light bones for flying.
118Survey of the Diversity of Life
5. Class Mammalia
i. Warm blooded and four-chambered heart.
ii. Endothermic—warm blooded.
iii, Hair and mammary glands.
iv. Development of offspring within mother prior to live birth.
F. Major Plant Divisions
1. Division Bryophyta—Non-vascular seedless plants.
i. Moss, liverworts, hornworts.
ii. Grow in moist conditions because of lack of vascular
system.
iii, Flagellated sperm that require water so they can swim to
the egg.
iv. Gametophyte is dominant life cycle.
2. Division Pteridophyta—Vascular seedless plants.
i, Ferns
Spores born on underside of leave.
iii, Sporophyte is dominant life cycle.
3. Phylum Coniferae—vascular seed plants
i. Called gymnosperms.
ii, Douglas Fir, Cedar, and other woody plants.
iii. Cone-bearing plants.
iv. Sporophyte is dominant life cycle
4, Phylum Anthophyta—vascular seed plant.
i. Called angiosperms or flowering plants.
ii, Formation of flower allowed for co-evolution with other
organisms.
iii. Sporophyte is dominant life cycle
was a major evolutionary adaption for birth to happen
~ 4 Organisms and Population—The terrestrial amniotic egg
\
CG outside of water.
119Jaydeyd
Phylogenetic
Classification
Diversity of Organisms—Phylogenetic Classification
A. Taxonomy—Classification of Organisms
1, Developed by Carolus Linnaeus and based on similarity of
organisms.
2. Hallmark is binomial nomenclature or genus species (Homo
Sapien).
Kingdom (most inclusive)
Phylum
cass
Order
Family
Genus
Species,
B. Major Kingdoms
1. Animalia
i, Animals are multicellular with organ systems.
ii. Cells have organelles including a nucleus, but no
chloroplasts or cell walls.
121Chapter 26
Move with the aid of cilia, flagella, or muscular organs.
iv, Heterotrophic—must ingest other organisms for
sustenance.
2. Plantae
i, Plants are multicellular with organelles including
chloroplasts and cell walls.
ii. Nutrients are acquired by photosynthesis (autotrophic).
3. Protista
i. Protists are single-celled organisms.
Move by cilia, flagella, or by amoeboid mechanisms.
iii, There is usually no cell wall, although some forms may
have a cell wall.
iv. May have chloroplasts.
v. Nutrients are acquired by photosynthesis, ingestion of
other organisms, or both (autotrophic and heterotrophic).
4. Fungi
i. Fungi are multicellular (except yeast, which are unicellular),
with a cell wall but no chloroplasts.
ii, Contain filamentous structures called hyphae for growth.
iii. Can be haploid and/or diploid (some have stages of both).
iv. Can reproduce asexually via spore formation.
v. Saprobic.
5. Monera
i, Monerans are single-celled, contain a cell wall, have no
chloroplasts or other organelles.
ii, Nucleoid.
iii, Haploid.
iv. Include Archaea and Eubacteria.
C. Domain System—developed in 1990 by Carl Woese and places
prokaryotes into 2 domains. Domains are more inclusive than
kingdoms (see Chapter 21).
1. Domain Bacteria
i. Kingdom Monera
2. Domain Archaea
i, Kingdom Monera
122Phylogenetic Classification
3. Domain Eukarya
i. Kingdom Protista
ii. Kingdom Fungi
iii, Kingdom Plantae
iv. Kingdom Animalia
Organisms and Population—The domain system of
classification is fairly new when compared to the kingdom
system. Even though the domain system is more inclusive, test
questions can be derived from both forms of classification.
123Evolutionary
Relationships
Jaydeyd
Diversity of Organisms—Evolutionary Relationships
A. Sedimentary Rocks
1.
Fossil record—strata that are formed are based on time. Top
strata contained the most recent fossil record, while bottom
strata contain older fossils.
B. Molecular Biology
1.
2.
Protein comparison—homology of the primary amino acid
structure.
DNA and RNA comparisons
i. DNA-DNA hybridization—measuring the extent of
hydrogen bonding between DNA of two different sources.
ii, Restriction Enzyme Mapping—restriction enzymes
recognize and cut sequences of DNA. A pattern can be
observed using DNA gel electrophoresis.
iii, DNA sequence analysis—comparing nucleotide sequence.
C. Cladistics
1.
A clade is a group of organisms that includes an ancestor
and all descendents of that ancestor. Cladistics is based on
molecular techniques (DNA and RNA sequences) rather than
morphology or form and structure of animals.
125Chapter 27
Species B
Shedding of tall
Enlarged cranium
Bi-pedalism
> Species B and C are more closely related to each other
than to species A.
> All species are generated from an ancestor species with bi-
pedalism.
» All species retain traits from the ancestor but have evolved
to gain some specific trait through time.
Organism | Bi-pedal | Large Cranium | Tail Loss
Species A x
Species B x
Species C x x x
126Plants and Animals—
Reproduction, Growth,
and Development
Jaydeyd
Reproductive Process of All Land Plants
A. Alternation of Generations
1, Two main multi-cellular forms called gametophyte and
sporophyte.
2. Gametophyte is haploid and produces the egg and sperm.
3. Sporophyte is diploid formed by the fusion of egg and
sperm.
4. Meiosis produces the spore that will eventually give rise to
sporophytes via mitosis.
5. Fertilization of male and female gametophyte produce a
sporophyte.
{ (muttictilar)
Mitosis * Meiosis
Tygote
“ar | (> >
an
otal
127Chapter 28
The Rise of Land Plants
A. Green Algae
1. Gave rise to land plants.
2. Most live in fresh water, but there are some marine (not a
land plant).
3. No vascular tissue or root system.
B. Bryophytes
1. Moss, liverworts, hornworts.
2. None vascular and seedless.
3. Have no root system, but are anchored via rhizoids or non-
vascular containing cells.
4. The dominant stage during the lifecycle of bryophytes is the
gametophyte,
i. Antheridia—produces the male gametophyte
Archegonia—produces the female gametophyte
iii. Fertilization takes place in the archegonia. Water
droplets are required to transport male gametophyte to
archegonia.
iv. Sporangium produces spores that will eventually produce
the mature male or female gametophyte.
C. Tracheophytes
1, 4 major characteristics
i. Protective layer that surrounds the gametes.
ii, Multicellular embryos.
iii, Cuticles or waxy layer that covers all parts above the root
system.
iv. Vascular system (xylem and phloem)
D. Pteridophytes (most basic tracheophytes)
1, Ferns and horse tails.
2. Vascular and seedless.
3. The dominant stage during the life cycle of pteridophytes is
the sporophyte.
128Plants and Animals—Reproduction, Growth, and Development
i, Antheridia—produces the male gametophyte.
ii, Archegonia—produces the female gametophyte.
4, Water droplets are required to transport male gametophyte
to archegonia.
5. Sporangia are found on the underside of the leaf and
produce spores that will undergo fertilization.
E, The Seed
1. Allows for protection.
2. Seed = sporophyte embryo along with a food source.
3. Seed can remain dormant but viable until favorable
conditions are met.
4. Dispersal via wind or animals.
F. Gymnosperm—conifers or cone-bearing plants such as pine.
1. The dominant stage during the life cycle of gymnosperms is
the sporophyte.
2. Ovule—structure containing the eggs that are produced via
meiosis.
3. Pollen Cone—pollen grains (haploid) are produced via
meiosis.
4. Ovulate Cone—contains two ovules.
5. Pollen Grain—2 male gametophytes formed via pollination
land on ovulate cone. One will be destroyed while the other
will wait at least one year before fertilization takes place.
6. Once a new embryo (only 1 of the eggs is fertilized) is
produced (sporophyte), a seed coat will be produced and
the unfertilized female gametophyte will become the food
reserve,
G. Angiosperm—flowering plant.
1. The dominant stage during the life cycle of angiosperms is
the sporophyte.
2. Reproductive structure of angiosperms is the flower.
i. Sepal—enclose and protect the flower before it buds.
ii, Petal—bright-colored structure that attracts insects for
pollination.
129Chapter 28
Stamen—male reproductive organ.
Carpel (pistal)—female reproductive organ.
v. Anther—part of the stamen where pollen is produced via
meiosis.
i. Stigma—part of the carpel; receives the pollen.
|. Style—part of the carpel that leads to the ovary.
Ovary—part of the carpel where the ovule is encased.
3. Fruit—a mature ovary.
i. After fertilization, the ovary thickens to aid in protection.
ii, Fruits aid in dispersing seeds because some are edible
by other species. Once eaten, the seed’s protective coat
will not break down and the organism will pass the seed
through feces at a distant location from where it was
eaten. The feces also contain a plethora of fertilizer that
will aid in germination.
4. Double fertilization and the endosperm
i, In contrast to gymnosperms where one of the pollen
grains is destroyed, both pollen grains fertilize one egg in
angiosperms. This is called double fertilization.
i. The triploid nucleus will continually divide giving rise to a
rich food reserve called the endosperm.
iii. Cotyledon or seed leaves are produced. Monocots produce
1 seed leaf while dicots produce 2 seed leaves.
Organisms and Population—Be sure to know the four
main plant groups: bryophytes, seedless vascular plants,
gymnosperms, and angiosperms. The gametophyte is the
dominant generation of bryophytes, while the sporophyte is
dominant in seedless vascular plants. In seed plants, such as
gymnosperms and angiosperms, the seed replaces the spore
4s the main means of dispersing offspring.
Animal Reproduction
A. Various Types of Reproductive Patterns
1. Asexual reproduction—no genetic diversity since all genes
come from one parent. No fusion of egg and sperm.
i, Budding—outgrowths from a parent form and pinch off to
live independently.
130Plants and Animals—Reproduction, Growth, and Development
ii. Binary Fission—a type of cell division by which prokaryotes
reproduce; each daughter cell receives a single parental
chromosome.
iii, Fragmentation—breaking of a body piece that will form an
adult via regeneration of body parts.
2. Sexual reproduction—genetic diversity since genes will be
inherited from both parents. Fusion of egg and sperm.
. Parthenogenesis—egg develops without being fertilized.
4, Hermaphroditism—having both male and female reproductive
organs.
w
B. Spermatogenesis (happens in gonads)
1. Continuous throughout the life of a male.
2. 4 viable sperm produced via meiosis in the testes.
C. Oogenesis (happens in ovary)
1. After first meiotic division cytokinesis is unequal with the
secondary oocyte receiving all of the cytoplasm from the
oogonium.
2. At birth the ovary contains all cells that will develop into the
egg.
3. Only 1 viable ovum is produced with 3 non-viable polar
bodies.
D. The Reproductive Cycle of the Human Female
1, Menstrual cycle or changes in the uterus or female
reproductive organ.
2. 28-day cycle in which the destruction and regeneration of
the uterine lining (endometrium) occurs.
i. Menstrual Phase (day 0-5)—menstruation (bleeding due to
destruction of endometrium).
|. Proliferative Phase (day 6-14)—regeneration of
endometrium.
Secretory Phase (day 15-28)—endometrium becomes more
vascularized and is ready for implantation of embryo. If
the embryo is not implanted, the entire menstrual cycle
will happen again.
131Chapter 28
132
3. Ovarian Cycle—parallels the menstrual cycle.
i. Follicular Phase (day 0-13)—egg cell enlarges in a follicle.
ii. Ovulation (day 14)—oocyte is released and pregnancy can
take place.
iii. Luteal Phase (days 15-30)—the corpus luteum is formed.
Astructure that grows on the surface of the ovary where
a mature egg was released at ovulation. The corpus
luteum produces progesterone in preparing the body for
pregnancy.
4. Important hormones
i. Gonadotropin-releasing hormone—aids in the release of FSH
and LH.
ii, Luteinizing hormone (LH)—stimulates ovaries.
iii. Follicle-stimulating hormone (FSH)—stimulates production
of ova (ovulation) and corpus luteum.
iv. Estrogen—stimulates uterine lining growth.
v. Progesterone—stimulates uterine lining growth.
Animal Development
A. Fertilization
1. Process of egg and sperm fusion to make a zygote,
2. Activation of egg that will lead to embryonic development.
B. After Fertilization
1. Cleavage—a series of rapid cell divisions to form blastomeres
(blastula) or small cells with their own nucleus.
2. Cleavage is the succession of rapid cell divisions without
growth during early embryonic development which converts
the zygote into a ball of cells.
3. When the blastomere reaches the 16-32 cell stage, it is called
a morula.
4. The morula will then become a gastrula by gastrulation.
The gastrula will form the three embryonic tissues of the
ectoderm, endoderm, and mesoderm.Plants—Structural,
Physiological, and
Behavioral Adaptations
Jaydeyd
Structure and Function of Plants—Structural,
Physiological, and Behavioral Adaptations
A. Diversity of Angiosperms
1. Monocots and dicots
Part Monocot Dicot
Embyro One cotyledon Two cotyledons (di)
(mono)
Leaf Venation | Parallel Net like
Stems Complex Ring arrangement
arrangement of of vascular bundles
vascular bundles
Roots Fibrous root Taproot
Flowers Flowers in Flowers in multiples
multiples of 3 of 4or5
B. Cell Types
1. Parenchyma cells—perform the metabolic processes of cells.
2. Collenchyma cells—support the plant.
3. Sclerenchyma cells—rigid cells that are found in areas where
the plant is no longer growing.
C. Tissue Types
1. Vascular-xylem tissue
i, Type of vascular tissue that transports water and dissolved
minerals from the roots up the plant.
|133Chapter 29
134
ii, Tracheids and vessel elements—dead cells that conduct
water and minerals.
2. Vascular-phloem tissue
i. Type of vascular tissue that transports food from the leaves
to the roots of the plant.
li. Sieve-tube members—live cells, but have no organelles.
Main function is to transport sucrose.
Companion cells—next to sieve-tube member and provide
all the metabolic resources for the sieve tube members.
Xylem works upward; Phloem works downward!
3. Dermal Tissue—protects the plant.
i. Cuticle—waxy coat that helps the plant retain water.
4. Ground Tissue—occupies space between vascular and dermal
tissues
i. Mostly made up of parenchyma cells.
D. Plant Growth
1. Apical meristems or primary growth—located at the tips of
roots or shoot buds and contain the cells undergoing mitosis
for vertical or expansive cell growth.
2. Lateral meristems or secondary growth—located through
the length of the shoot system and roots and is considered
outward horizontal growth (increases plant’s diameter).
Organisms and Population—Memorize! Memorize!
Memorize! Do not lose points because you forgot the
properties of plant cells and tissues.Animals—Structural,
Physiological, and
Behavioral Adaptations
Jaydeyd
Structure and Function of Animals—Structural,
Physiological, and Behavioral Adaptations
A. Mammalian Digestive System
1. Oral Cavity (only carbohydrates are broken down)
i, Mouth secretes salivary amylase which breaks down
starch. Chewing or mechanical digestion is also carried
out. Bolus or ball of food is formed.
ii. Pharynx, or back of the throat, has a structure called the
epiglottis that blocks food from going down the windpipe
or trachea.
Esophagus—food tube that conducts bolus down to the
stomach via a smooth muscle contraction called peristalsis.
2. Stomach (only protein is broken down)
i. Gastric Juice—a digestive fluid with pH of about 2 that aids
digestion.
ii, Pepsin—a protease secreted in an inactive form called
pepsinogen until food is present in the stomach.
iii, Acid Chyme—food and gastric juice that is processed in the
stomach.
3. Small Intestine and Accessory Organs (all 3 macromolecules
are broken down)
i, Organ that digests most food and absorbs it into the
blood.
ii, Duodenum—first part of the small intestine where
digestion takes place.
Pancreatic enzymes are sent to the small intestine to
aid in digestion. These enzymes are protease, amylase,
and lipase. Bile from the liver (stored in the gallbladder)
|135Chapter 30
emulsifies or opens up the fat for lipase to break it down.
Fat is broken down for the first time in the small intestine.
iv. Microvilli of the small intestine increase the surface area
and allow for absorption of nutrients.
4, Large Intestine or Colon (No Digestion)
i. Main purpose is for reabsorption of water.
ii. Feces are created and eliminated through the rectum or
end of the large intestine.
B. Circulatory System
1. Open Circulatory System—blood mixes with internal organs
directly. Insects, arthropods, and mollusks have an open
circulatory system.
2. Closed Circulatory System—blood is confined to blood vessels
that lead to the organs. Earthworms, octopi, and vertebrates
have a closed circulatory system.
3. Fish—one ventricle, one atrium with gill capillaries allowing
for gas exchange.
4. Amphibian—one ventricle and two atrium; have lung and
skin capillaries for gas exchange. Have double circulation or
oxygen-rich blood going to the organs and oxygen deficient
blood returning to the right atrium.
5. Mammal—two ventricles and two atrium, with lung
capillaries for gas exchange. Also makes use of double
circulation.
6. Flow of Blood in Mammalian Heart
i, Deoxygenated blood from the vena cava enters the right
atrium and passes through the right atrioventricular valve
(tricuspid valve) into the right ventricle. From the right
ventricle it travels out of the heart via the pulmonary
artery where it becomes oxygenated at the lungs (CO,
is exchanged for O,). Oxygenated blood then travels via
the pulmonary vein to the left atrium and through the left
atrioventricular valve (mitral or bicuspid valve) into the left
ventricle. Oxygenated blood then leaves the left ventricle
of the heart via the aorta to the organs of the body.
7. Beating of the Heart
i. Cardiac muscle transfers an electrical signal via the
following: Sinoatrial (SA) node or “pacemaker” of the
136Animals—Structural, Physiological, and Behavioral Adaptations
8.
heart (top of right atrium) generates an electrical impulse
that is relayed to the atrioventricular (AV) node located
between the right atrium and right ventricle. The signal
then transfers to the bundle branches and Purkinje fibers
at the heart’s apex.
Blood Pressure
i. The force of blood against a blood vessel wall is a measure
of blood pressure.
ii. Systolic pressure is peak pressure in the arteries, which
occurs when the ventricles are contracting. Diastolic
pressure is minimum pressure in the arteries, which occurs
when the ventricles are filled with blood. The ratio of
systolic and diastolic pressure is the measurement of blood
pressure (systolic pressure/diastolic pressure).
C. Respiratory System
Us
2.
3.
Gas exchange is defined as the uptake of oxygen (O,) and
loss of carbon dioxide (CO,).
Gills—specialized for gas exchange of aquatic organisms.
Tracheal system and lungs—specialized for gas exchange of
terrestrial organisms. For an insect such as a grasshopper, the
tracheae opens to the outside.
.. Lungs—Amphibians (frogs) are the only vertebrates that use
skin along with lungs to promote gas exchange.
. Flow of Air in Mammalian Lungs
i. Inhaled air passes through the /arynx (upper part of the
respiratory tract) into the trachea or windpipe (rings of
cartilage). The trachea divides into two bronchi leading
to the lungs. The bronchi branch to bronchioles which
contain air sacs called alveoli. The alveoli are covered with
capillaries where the gas exchange will take place.
. Control of Breathing
i. Medulla oblongata, lower part of the brainstem, maintains
homeostasis by monitoring CO, levels. When CO, levels
are high, the CO, reacts with water in the blood, dropping
the pH of the blood. The medulla oblongata senses a pH
drop and excess CO, is exchanged for O,..
. Hemoglobin
i. Iron—containing protein of mammalian red blood cells.
|137Chapter 30
D. Immune System
1. First Line of Defense (non-specific)
i, Skin
ii. Mucous
2. Second Line of Defense (non-specific)
Inflammatory Response
i. Antimicrobial Proteins
3. Third Line of Defense (specific)
i, Lymphocytes (T and B cells)
ii, Antibodies
4. Immune Response
i. Primary Immune Response—first exposure to antigen
(foreign molecule) requires 10-15 days for lymphocytes to
generate the maximum response.
i. Secondary Immune Response—second exposure to
antigen requires less time to react to antigen. The
response is greater and longer. This response is based on
immunological memory that the immune system retains
after the primary exposure.
Secondary
Immune
Response:
First exposure
toantigen
3 10005
ig
5§ 10
SE
z= | fae | seconde
al toantigen
:
fel
0 » 0 60
Time (days)
5. Self vs. Non-self
i. One of the hallmarks of the immune system is to
distinguish self from non-self. Immune cells and other
body cells coexist in a state known as self-tolerance.
6. Passive and Active Immunity
i. Active Immunity—immunity gained by recovering
from a disease. Can also be gained from vaccination
(immunization).
138Animals—Structural, Physiological, and Behavioral Adaptations
ii, Passive Immunity—immunity gained by one individual
passing antibodies to another.
7. Antibody Structure
i. Y-shaped proteins that bind antigens at specific antigenic
determinants called epitopes.
ii. 5 types of antibodies:
» IgG—most abundant antibody, crosses the placenta
and gives passive immunity to fetus.
» IgA—present in body secretions such as saliva and
tears.
» IgM—first antibody in the primary immune response.
> IgD—found on the cell surface of B cells
» IgE—released in response to allergic attacks.
E. Control Systems
i
Thermoregulation
i. Body Insulation—hair, feathers, and fat reduce heat loss.
ii. Vasodilation—increased blood flow to the skin, causing
heat loss.
iii. Vasoconstriction—decreased blood flow to the skin,
reducing heat loss.
iv. Cooling—sweating or panting.
v. Behavorial—organism can move to a warmer or colder
region.
Hibernation—decreased body temperature because of
decreased metabolic activity.
vi.
F, Urinary (Excretory) System
Us
Malpighian Tubules—excretory organs of insects and
arthropods.
2. Mammalian Kidney—bean-shaped organ (mammals have 2).
139Chapter 30
i, Blood enters the kidney via the renal artery and leaves the
kidney via the renal vein.
ii. Urine leaves the kidney and enters the bladder via the
ureter.
|. Urine in the bladder is excreted via the urethra.
. Renal medulla—inner portion of the kidney
v. Renal cortex—outer portion of the kidney
3. Nephron—basic structural and functional unit of the kidney
(roughly 1 million per kidney).
4. Nitrogenous Waste Products
i. Ammonia—aquatic animal waste (very toxic and would be
deadly for terrestrial animals).
ii, Urea—mammalian and amphibian waste that breaks down
to form ammonia.
iii, Uric Acid—birds, snails, insects, and reptiles.
5. Production of Urine
i. Glomerulus—renal artery becomes a ball of capillaries
surrounded by a Bowman’s Capsule within the nephrons
of the kidneys, which collects fluids (filtrate) as they pass
through the glomerulus.
i. The filtrate will pass through proximal tubule, loop of Henle,
and distal tubule.
Urine is gathered in the collecting duct, where it empties
into the urinary bladder via the ureter.
G. Nervous System
1, Central Nervous System (CNS)—brain and spinal cord.
2. Peripheral Nervous System (PNS)—all other nervous system
structures outside the CNS.
3. Neuron—basic unit of nervous system.
i. Cell Body—large portion of neuron that contains the
nucleus and organelles.
ii, Dendrites—communicate the nervous signal from tips of
neuron to the cell body.
Axon—conduit that communicates down the neuron
away from the cell body.
iv. Myelin Sheath—lipid-based insulation around the
Schwann cells that stops the leaking of the nervous signal.
140Animals—Structural, Physiological, and Behavioral Adaptations
v. Schwann Cell—chain of cells that propagates the nervous
signal.
vi. Node of Ranvier—space or gap between the Schwann
cells.
vii. Synapse—the space between the end of the axon and
the target; examples of targets include muscles or other
neurons.
4, Passage of a Nerve to a Reflex Action
i. Signal — Sensory Receptor — Sensory Neuron >
Interneuron -> Motor Neuron -> Muscle
|. Presynaptic Membrane—surface of synaptic terminal that
faces the synaptic cleft. Neurotransmitter (packaged in a
vesicle) will be released across the cleft to a postsynaptic
cell via the presynaptic membrane.
Postsynaptic Membrane—surface of the cell body/axon
that is on the opposite side of the synapse. Will receive
the neurotransmitter and depolarization of the neuron will
take place, thus propagating the signal.
eft
Presynaptic Cell | Postsynaptic Cell
5. Action Potential—the threshold required to be reached in
order for an all or none change in the membrane potential of
a neuron to occur
i. All neurons have a charge associated with them because
of the concentration of various ions being transported into
and out of the cell. A cell at rest has a resting membrane
potential of approximately -70mV. Both Na* and K*
channels are closed.
ii, Depolarization—reduction in the absolute value of
membrane potential because Na* channels open and flood
inside of the cell. K* channels are closed.
|. Action Potential—if depolarization hits the threshold, an
action potential will be created. This is the example of the
all or none event.
iv. Repolarization and hyperpolarization—decrease in
membrane potential (more negative) because K* channels
\141Chapter 30
open and K* leaves the cell. Na* channels are closed.
Returns the membrane potential from positive (caused by
depolarization) to negative.
Depolarization and
Acton Potential ae
Theeshold
i
i
esting Frpepolaztion
Potential ail
Time (msec)
6. Neurotransmitters—chemicals that are released at synapses.
i, Acetylcholine—can be inhibitory or excitatory. When
the target cell is a muscle, then it is usually excitatory.
Acetylcholinesterase is an enzyme that destroys
acetylcholine.
. Norepinephrine and Epinephrine—involved in flight or fight
response and generally excitatory.
7. Parts of the brain
i. Medulla oblongata—controls breathing, circulatory system,
and digestive system.
ii. Pons—accessory portion of brain that controls breathing.
ii. Cerebellum—controls movements and coordination, i.e.,
hand-eye coordination.
iv. Cerebrum—part of the forebrain and regulates the
conscious functions of the body such as thought and
reasoning and perception of stimuli.
v. Cerebral cortex—key role is memory.
vi. Corpus callosum—facilitates communication between the
right and left hemispheres of the brain.
vii. Hypothalamus—regulates body temperature, hunger, and
thirst.
142Animals—Structural, Physiological, and Behavioral Adaptations
H. Endocrine System
1, Major Glands and Tissue
Hypothalamus—inks the nervous and endocrine systems
by receiving signals and propagating the endocrine
response. Located in the lower half of the brain.
Pituitary gland—“master gland”; many of the hormones
released by the pituitary gland communicate with
other glands. The pituitary is under control of the
hypothalamus.
Thyroid gland—located near the trachea.
Parathyroid gland—located on surface of the thyroid.
v. Pancreas—near the kidneys and contains specialized cells
called Islets of Langerhans that secrete hormones.
vi. Adrenal gland—tocated on top of the kidneys.
vii. Gonads—testes and ovary.
viii. Pineal gland—small peanut-shaped gland near the center
of the brain.
ix. Thymus—located in the upper portion of the chest cavity.
Gland Hormone Action
Pituitary Oxytocin Contraction of uterus;
breast milk let-down
Pituitary Antidiuretic hormone | Water retention in
kidney
Pituitary Growth Hormone Stimulates growth
Pituitary Prolactin Stimulates milk
production from
mammary gland
Pituitary Follicle Stimulating Stimulates production of
Hormone ova and sperm
Pituitary Luteinizing Hormone | Stimulates ovaries
(continued)
143Chapter 30
Gland
Pituitary
Thyroid
Thyroid
Parathyroid
Pancreas
Pancreas
Adrenal
Gland
Testes
Ovaries
Ovaries
Pineal
Hormone
Thyroid Stimulating
Hormone
Triiodothyronine (T,)
and thyroxine (T,.)
Calcitonin
Parathyroid Hormone
Insulin
Glucagon
Norepinephrine and
Epinephrine
‘Androgens
Estrogens
Progesterone
Melatonin
Action
Stimulates the thyroid
Stimulates metabolism
Lowers calcium level in
bloodstream; stimulates
bone construction
Raises blood calcium
Lowers blood glucose
Raises blood glucose
“Fight or Flight”
response; stimulates
metabolism
Promote sperm
formation and
secondary male
characteristics
Stimulate uterine lining
and secondary female
characteristics
Stimulate uterine lining
growth; maintains
pregnancy
Sleep-wake cycle and
other circadian rhythms
|. Sliding Filament Model of Muscle Contraction
1. Interaction of two proteins called myosin and actin.
2. Myosin binds to actin and simultaneously ATP will be
hydrolyzed.
144Animals—Structural, Physiological, and Behavioral Adaptations
3. An interaction between myosin and actin causes the actin
filaments to be moved (sliding) and muscle contraction to
take place.
4. Ca** ions are essential ions needed for the entire process to
take place.
Al
Test ga /. Organisms and Population—All the systems of the body
Tip come together to maintain the homeostasis of the body.
This is a central theme in the AP Biology curriculum.
145Plants—Response to
the Environment
Jaydeyd
Structure and Function of Plants—Response to
the Environment
A. Transport of Water and Minerals in Plants
1. Water Potential 1p—combination of both solute
concentrations and pressure. Water will always flow from a
high water potential to a lower water potential.
2. Equation for water potential ) = Wyresssure + VPsome
3. Plasmodesmata—channels between plant cells that allow the
flow of fluids.
4. Flow of water in roots begins at the root hair or extensions of
the epidermal cells.
i, From the root hair water will travel to the epidermis, cortex,
the endodermis, and stele which contain xylem cells.
ii. Casparian strip—a waxy lipid found in the endodermis that
repels water and forces it into the stele.
5. Mycorrhizae—symbiotic relationship between plant roots and
fungus that assists the plant in transferring water.
B. Transpiration
1. Transpiration—loss of water through the plant leaf.
2. Xylem sap—water and dissolved inorganic ions that ALWAYS
flow from the roots of the plant to the leaves.
3. Guttation—xylem sap that can be found as droplets on
leaves.
4. Root Pressure—forcing of water up the xylem as a result of
water entering the root system via osmosis. Guttation is the
main result of root pressure.
|147Chapter 31
5. Transpiration—Cohesion-Tension Model
i. Water is taken up by the root system of the plant
(transpiration).
. Cohesion of water molecules to each other and the
adhesion of water to the cell wall start the ascent of water
up the plant (cohesion).
|. The top of the plant has a lower water potential than the
bottom of the plant. Water travels up the plant based on
the water potential gradient.
iv. As more water leaves the plant leaf via transpiration, the
water potential becomes more negative (this is called
tension) driving even more xylem sap up the plant.
6. Regulation of Transpiration
i. Guard cells—open and close the stomata of the cell, which
changes the amount of gas exchange and water loss.
C. Translocation
1. Translocation—transport of food (phloem sap) in the plant via
phloem.
2. Sink-Source Model
i. Source Cell—cell that produces sucrose via photosynthesis.
These are mesophyll cells, which are found in the leaf.
i. Sink Cell—cell that will consume or store sugar. These cells
are roots, stems, and fruits.
iii, Sugar from the source is loaded into the sieve tube
members and is transported down the phloem via
pressure flow.
iv. Phloem sap will reach the sink cells where sucrose will
be transported into the sink. The water that assisted to
transport the sucrose will be recycled to the xylem cell and
move up the xylem.
D. Plant Hormones
1. Auxin—stimulates stem elongation, development of fruit, and
root growth.
2. Abscisic acid—inhibits growth.
148Plants—Response to the Environment
3. Ethylene—promotes the ripening of fruit.
. Cytokinins—stimulated cell division, growth, and germination.
5. Gibberellic acid—stimulates the flowering of a plant and the
development of fruit.
*
E, Tropisms
1. Phototropism—plant growing toward light. Main hormone
that allows this is auxin.
2. Gravitropiim—growing in response to gravity. Positive
gravitropism is exhibited by roots since they grow
downwards. Shoot systems of plants exhibit negative
gravitropism or growth against gravity.
3. Thigmotropism—directional growth of plants growing around
structures, such as vines on walls.
F, Photoperiodism—response of a plant to the length of day and
night (a circadian rhythm)
1. Short-day (long-night) plant—requires a longer amount of
darkness to bloom. This type of plant will bloom when the
amount of darkness exceeds the critical night length.
2. Long-day (short-night) plant—requires a shorter amount of
darkness to bloom. This type of plant will bloom when the
amount of darkness is less than the critical night length.
G. Phytochromes—pigments that plants use to detect light.
1. Phytochromes are sensitive to red and far-red light.
2. Red light promotes the growth of long-day plants, but
inhibits short-day plant growth.
3. A burst of far-red light following red light can reverse the
effects of the red light.
Al
Test $2“. Organisms and Population—The sink-source model is a
Tip G) great example of structure and function with the key molecule
being water.
149Biosphere
Jaydeyd
Ecology—Biosphere
A. Abiotic Factors—non-living physical or chemical factors.
Temperature, light, weather.
B. Biotic Factors—living factors. Organisms in an environment.
C. Levels of Ecological Organization—biosphere is more inclusive
than individual.
Biosphere
Community
=
fo
Individual
151Chapter 32
152
Terrestrial Biomes
Biome
Tropical
Rain Forest
Major Location
South America
Features
* Tremendous organic
diversity
High rainfall
Poor soil because of high
rainfall
Canopy or topmost layer
is made of trees that block
sunlight
Slash and burn techniques
commonly used
Very low temperature range
.
.
.
.
Desert
Northern Africa
Southwest U.S.
Australia
Little rainfall
Cacti and other water-
storing plants found (i.e.,
succulents)
Usually hot, but there are
cold deserts (i.e., Antartican
Desert)
* No canopy
Plants are spiny for
protection
Savanna or
the tropical
grassland
Central and
South Africa
.
Large herbivores
Dominant herbivores are
insects
Grasses, patches of trees
are major plants
Seasonal droughts with dry
and wet seasons
Warm temperature year
round
.
.
.
°
Chaparral
West coast of
esa
Known for wildfires
Sloping mountains with
shrubs,
Coastal area with hot, dry
summers and mild, rainy
winters
(continued)Biosphere
Biome Major Location | Features
Temperate | North American | ¢ Grass is major plant
Grassland | Prairies * Nutrient rich soil for
agricultural growth
* Grazing by large animals
* In the U.S., called farmland
Temperate | Northeast U.S. * Deciduous—falling of
Deciduous leaves prior to winter
Forest ¢ Hibernation for animals
because of 4 true seasons
* Hickory, oak, maple are
major trees
Coniferous | Upper North * Cone-bearing plants such
Forest or America or as pine
Taiga Canadian * Cold temperatures
Region * Moose, bear, deer
Tundra Upper North * Permafrost or permanently
America or frozen soil
Canadian © Very little rainfall
Region * Short growth season and
little diversity
* Moss and liverworts
dominant plants
(gymnosperms)
* Too cold for reptiles or
amphibians
Aquatic Biomes
A. Vertical Stratification
1. Upper Photic Zone—lots of light for photosynthesis.
2. Lower Photic Zone—low amount of light, therefore, little
photosynthesis but some still occurs.
3. Benthic Zone (Aphotic Zone)—bottom of aquatic biomes.
Benthos, or organisms that live at the bottom, feed on
detritus or dead organic matter. No light penetrates.
153Chapter 32
B. Freshwater Biome
1. Littoral Zone (part of Photic Zone)—located where aquatic or
root-based plants live. Close to shore.
2. Limnetic Zone (part of Photic Zone)—farther from shore where
phytoplankton live.
3. Profundal Zone (part of Aphotic Zone)—deep Aphotic region.
C. Wetland—any area covered with water that supports aquatic
growth. Can be flooded or have soil that is permanently
saturated during the growing season.
). Estuary—area where fresh and saltwater meet.
. Marine Biome
1. Intertidal Zone (part of Photic zone)—where land meets water.
2. Neritic Zone (part of Photic zone)—shallow water regions.
3. Oceanic Zone (part of Photic zone)—past the continental shelf
to far depths.
4. Abyssal Zone (part of Aphotic zone)—very deep benthic
communities that are very cold and have total darkness, with
no nutrients. No photosynthetic activity, therefore, primary
productivity is low.
vl
Test ), Organisms and Populatlon—There is a multitude of
Tip \~ information regarding biomes in this chapter. Any one of these
154
facts could be in a multiple-choice question or be used as
supporting evidence for an essay.Jaydeyd
Population
Dynamics
Ecology—Population Dynamics
A. Population Density—number of people per unit area.
B. Dispersion—how individuals in a population are spaced per unit
area.
1. Clumped—individuals are aggregated in patches or groups.
XXX
XXX
Example is a school of
XXX XXXX fish or pride of lions.
XXX
2. Random—arbitrary pattern of individuals.
x x
_ Example could be
=> a population of ants
x on a sidewalk.
x x
ie x
155Chapter 33
3. Uniform-pattern based, or evenly spaced individuals.
x x x
x
ng x x Example is a forest of
x => trees that follow a
pattern.
x x x
x
C. Survivorship Curve—simple graph of the number of individuals
alive at certain ages.
A
Type —Death occurs for the
elderly (ie, humans)
‘Type Il—Death independent
1 ofage (Le, fish o bitds)
Survivors
‘Type l—Death occurs for the
young (ie, plants or sea anemone)
Time
D. Population Growth Models
1. Exponential Model—unlimited growth of the population
because of no limitation on resources. The result is a J-shaped
curve,
156Population Dynamics
Population
Size
Number of Generations
2. Logistic Model—limited growth of the population because of
limited resources. The result is an s-shaped curve. The carrying
capacity or the maximum population size that a habitat can
hold (defined by the letter K).
Population
Size Canrying Capacity
Exponential
‘<—_— iowrth
orLog Phase
Number of Generations
3. K-selected population—have a density near their resources or
their carrying capacity. For example, humans.
4. r-selected population—a population that grows fast,
reproduces fast, and dies rather quickly. For example,
bacteria.
157Chapter 33
158
K-selected population
Slow sexual maturation
Long life span
Large offspring
Type | survivorship curve
Sexual reproduction
r-selected population
Rapid sexual maturation
Short life span
Small offspring
Type Ill survivorship curve
Asexual reproduction
. Density-dependent factors—A factor that affects population
size based on the density of population. Most likely biotic
factors such as food, predation, migration, or disease.
. Density-independent factors—A factor that affects the
population size regardless of density. Most likely abiotic
factors such as weather or natural disaster.
Organisms and Population—The logistic model of growth
can be applied to bacterial growth as well as viral growth. It
is commonly used with those examples.Communities and
Ecosystems
Jaydeyd
Population Interaction—interactions that occur
with different species living in a community
(conglomerate of different species living in one
location).
A. Predation—predator eats the prey. One species benefits while the
other does not.
1. Adaptations for predator—claws, teeth, poisons, speed,
eyesight.
2. Adaptations for prey plants—thorns in plants, plant chemicals
that ward off prey.
3. Adaptations for animals—cryptic coloration or camouflage,
aposematic coloration or bright colors that warn, or warning
noises.
4. Mimicry—prey resembles another species.
i. Batesian mimicry—a harmless species mimics a species that
is dangerous to the predator.
ji, Mullerian mimicry—two harmful species resemble each
other and create a cumulative effect against a predator.
B. Parasitism—parasite lives off the host. One species benefits while
the other does not (i.e., viruses, tapeworms, and mosquitoes).
C. Competitive Exclusion Principle—two species cannot survive in
the same ecological niche (the sum of the total abiotic and biotic
factors in an ecosystem). Neither species benefits from this
interaction.
D. Symbiosis—means living together between a host and a
symbiont.
159Chapter 34
160
1. Commensalism—One species benefits while the other is not
affected. An example is a clownfish that lives within a sea
anemone’s poison tentacles. The clownfish is protected and
the sea anemone is neither harmed nor benefited.
2. Mutualism—Both species benefit from the interaction.
Pollination between insects and plants.
Fungi and algae in lichen.
Rhizobium—bacteria living in the root nodules of plants
supplying the organism with amino acids, while accepting
carbon in the form of organic acids for respiration.
iv. Bacteria living in the gut of a cow secrete the enzyme
cellulase which helps break down cellulose for the cow.
The bacteria have a comfortable place to live, and the cow
receives nutrients from the broken-down cellulose.
3. Coevolution—the evolution of one species acting as a selective
agent for the evolution of a second species. An example
would be the co-evolutions of plants and insects.
Ecological Succession—Changes in the Composition
of a Community Over Time.
A
Primary Succession—Area starts off containing lifeless conditions,
such as a volcanic island or barren land. Initial pioneer species,
such as moss and lichen, colonize the area. Fertile soil develops
and grass, shrubs, and other plants begin to grow. This process
can take hundreds of years.
. Secondary Succession—Area has been destroyed by a natural
disaster, farming, or slash-and-burn techniques. The area returns
to its initial state because the fertile soil in the area has not been
removed. This process can be completed within one year.Communities and Ecosystems
Ecosystems—All the Organisms Living in a
Community, Including Abiotic and Biotic Factors.
A. Trophic Levels—division of organisms in an ecosystem.
1. Primary Producers—photosynthetic organism such as plants
and blue green algae.
2. Primary Consumers—herbivores or plant-eating organisms.
3. Secondary Consumers—carnivores that eat the primary
consumers.
4. Tertiary Consumers—carnivores that eat carnivores or
organisms below them.
5. Detritivores—derive their energy from dead organisms or
detritus (i.e., fungi and soil microbes). Extremely helpful in
recycling matter.
B. Food Chain—pathway in which food is transferred from one
trophic level to the next. Arrow points to the organism that is
“doing” the eating.
Terrestrial Food Chain ‘Marine Food Chain
161Chapter 34
162
C. Food Web—an elaborate web of organisms feeding at more than
one trophic level.
D. Energy Flow in Ecosystems
5
Primary Productivity—the amount of light energy converted to
chemical energy in an ecosystem, by autotrophic organisms.
Measured by the units of biomass or weight per unit area per
unit time (g/m?/yr).
2. Gross Primary Productivity—total primary productivity.
. Net Primary Productivity—the energy used by producers
for cellular respiration subtracted from the gross primary
productivity.
. Secondary Productivity—measurement of an organism’s intake
of energy that is converted to weight.
. Loss of Energy from a food chain—each time energy is taken in
by an organism at a particular trophic level, only 10% of that
energy is converted into a new biomass for the next trophic
level. This rule is called the 10% rule.Communities and Ecosystems
—— 10 Tertiary consumer
100) Secondary consumer
Primary consumer
voy
consumer
10,000 ) Primary consumer
100,000 J of ight energy
6. Pyramids of Biomass—because of the 10% rule, biomass
pyramids tend to follow the same scheme and shape.
Producers have the greatest biomass for the most part.
E. Cycling of Elements
1. Water Cycle—cycling of water through evaporation,
precipitation, percolation, and runoff.
2. Carbon Cycle—cycling of carbon through photosynthesis and
cellular respiration. Burning of fossil fuels is another source of
carbon dioxide in the atmosphere, as is volcanic action.
3. Nitrogen Cycle—nitrogen enters the cycle as atmospheric
nitrogen or through nitrogen fixation, or the conversion of
nitrogen into compounds that can be used, such as amino
acids or nucleic acids. Soil bacterium called rhizobium, found
in the root nodules of plants, uses nitrogen fixation.
4. Phosphorus Cycle—Phosphorus from the weathering of rocks
or soil is cycled around from one organism to another.
Organisms and Population—You need to understand the
differences between a food web and a food chain. A food
chain is exactly that—a chain of organisms that feed on each
other. A food web is more complex and actually indicates the
relationship among several different organisms that may feed
on one another.
163Ecology—Behavior
Jaydeyd
Ecology—Behavior
A.
Innate Behavior—all organisms exhibit certain behaviors that are
not learned, but are “built in.” (For example, a baby holding
onto its mother’s hand when born.) Usually not changed by the
environment.
. Fixed Action Pattern—set of behaviors that cannot be changed.
An example would be Nikolaas Tinbergen’s digger wasp
experiment in which the wasp located its nest based on
markings and visual cues.
.. Repertoire—series of songs that can be distinguished by
organisms and signal an action. Mostly done by birds for mating
purposes.
Learning—modifying your behavior based on specific events in a
lifetime.
. Habituation—loss of response to stimulus. For example, if a
certain animal hears the calls of a predator, but the predator
does not attack, eventually it will no longer respond to the
stimulus.
. Imprinting—learning a behavior at a specific time in an
organism's life. An example would be Konrad Lorenz’s becoming
the mother of young geese.
165Chapter 35
G. Classical Conditioning—learning associated with a reward or
punishment. Pavlov’s dog experiment: when the dogs heard the
sound of a bell at feeding time, they started to salivate for food.
Eventually, they were conditioned to salivate anytime they heard
the bell, independent of food being present or not.
H. Operant Conditioning—learning by trial and error. B.F. Skinner's
box experiment.
|. Kinesis—changing the rate of an action in response to a stimulus.
J. Taxis—movement away or toward a stimulus.
K. Territoriality—defending one’s area, for example by marking the
area and/or physical confrontation.
L. Communication—sending information from one organism to
another (or group of organisms). Chemical communication
can be done via pheromones or hormones that communicate
mating. A classic example is the dancing of bees to communicate
the location of food, discovered by Karl von Frisch.
M. Altruism—concern for the well-being of others or a group. This is
most often seen in kin relationships.
N. Hierarchy—certain members of the group have a higher standing
over other members. As a result, the members with a higher
status feed before others, and have their choice of a mate.
O. Group Size—flocks, schools, herds, or prides can all be methods
in which organisms organize themselves into groups. This allows
for increased hunting efficiency as well as protection. However,
the weaker members of the group may be subordinate to
stronger ones. Communicable diseases can also have deleterious
effects on the population numbers.
Organisms and Population—These terms may not seem to
be part of a biology course, but behavior is a key evolutionary
trait that will be tested on the AP Biology exam.Jaydeyd
Ecology—Global Issues
Ecology—Global Issues
A. Biological Magnification—toxic chemicals being increased in
concentration from one trophic level to the next. Biomass from
one level is created from a larger biomass from the trophic level
before. Top-level consumers are mostly affected. The best-known
example is the use of DDT pesticide.
B. Ozone Layer—the ozone layer absorbs harmful UV light. CFCs
or chlorofluorocarbons in aerosol cans and refrigeration units
destroy the ozone by reducing it to oxygen.
C. Greenhouse Effect—carbon dioxide emissions from the burning
of fossil fuels acts as a trap of solar heat in the atmosphere.
Increases in carbon dioxide warm the air and accelerate the
greenhouse effect. This is thought to be the major cause of
global warming. Deforestation is also a major contributor to the
greenhouse effect.
Organisms and Population—Environmental awareness is the
hallmark to the homeostasis of biomes that are both terrestrial
and marine.
167——— PART V:
THE EXAMMajor AP Biology
Themes and Their
Relationship to
the Exam
The AP Biology curriculum is unified by thematic underpinnings.
These underpinnings can be related to any of the topics that are
presented in this AP Biology Crash Course. A good way to utilize
these themes is to incorporate them into your essays. The AP Biol-
ogy readers will be delighted that you were able to see the big
picture of the course, rather than small isolated concepts. Below
are the major themes and some conceptual examples that apply
to them.
Major Themes
A. Science as a Process
1, The experiments of Watson and Crick and others that lead to
the discovery of DNA as genetic material;
2. The experiments of Gregor Mendel that lead to the basic
laws of genetics;
3. The experiments of Thomas Hunt Morgan that lead to linked
genes;
4, Miller-Urey experiment and its validation of the Oparin-
Haldane model of the primitive atmosphere.
B. Evolution
1. Fermentation as the precursor for cellular respiration;
2. The Endosymbiotic Theory and the development of the
eukaryotic cell;
3. The role of genetic variability in evolution: crossing over in
meiosis, mutations, independent assortment of gametes;
\171
JaydeydChapter 37
172
4. The adaptations of various animal phyla and plant divisions.
C. Energy Transfer
. Coupling of the four main processes of cellular respiration;
. The coupling of cellular respiration and photosynthesis;
. Hydrolysis of ATP in all 3 parts of the central dogma;
. The utilization of energy in ecosystems.
AWN
D. Continuity and Change
1. The presence of carbon in all macromolecules as a means of
continuity. However, the assimilation of carbon is different in
carbohydrates, lipids, proteins, and nucleic acids;
2. Mitosis as a means of continuity and meiosis as a means of
change;
3. The process of fertilization as a means of continuity
throughout the domains of life, but the specialization of cells,
tissues, and organs as a means of change after fertilization;
4. The overall structure of a biome is continuous while
populations can change based on abiotic and biotic factors.
E. Relationship to Structure and Function
1, The differences between the structure of DNA and RNA
leading to different cellular functions;
2. The homologous structures of body parts of organisms
having different functions;
3. The various structured organ systems of the human body and
their individual functions;
4. The structure of the genomes of eukaryotic and prokaryotic
species leading to different cellular functions.
F. Regulation
1. The membrane as a means of selective permeability;
2. The function of inducers and repressors in an operon system;
3. The methods by which organisms that are ectothermic and
endothermic regulate body temperature;Major AP Biology Themes and Their Relationship to the Exam
4, How various cycles such as water, carbon, and nitrogen
maintain homeostatic levels.
G. Interdependence in Nature
1. The global issues that can disrupt an ecosystem;
2. The use of water in moss and fern fertilization;
3. Sunlight as the driving force of photosynthesis;
4, The survival of the fittest concept that drives evolution.
H. Science, Technology, and Society
1. The use of recombinant DNA techniques in all aspects of
scientific inquiry;
2. Pollution in a technologically advanced society;
3. Global warming;
4. Deforestation results in overlapping ecological niches.
Themes—Use the themes to your advantage. If you mention
these themes in your essay, the essay scorer will surely award
you more points.
173The 12 AP Biology Labs
b 1 Diffusion and Osmosis
Jaydeyd
Presence of
ars Solution Color Glucose
Initial
Contents Initial Final Initial | Final
Bag 15% glucose | Clear Blue/ Yes | Yes
& 1% starch black
Beaker | H,O & IKI Yellowish | Yellowish | No Yes
Exercise 1A: Diffusion
The interpretation of this exercise was that starch is too large a
molecule to escape through the pores of the dialysis bag. As a
result, the dialysis bag turns from clear to blue/black because
the IKI from the beaker diffuses through the pores and reacts
with the starch (a positive test for starch). The beaker fluid
stays yellowish because no starch has diffused from the dialy-
sis bag. Glucose is present in the beaker because it is a smaller
molecule than starch and diffuses through the dialysis bag’s
pores. Residual glucose is still in the bag, thus you continue to
have a positive result for the bag.
175Chapter 38
Exercise 1B: Osmosis
Contents in Bag Percent Change
0.0 M Distilled Water 0.1%
0.2 M Sucrose 2.7%
0.4 M Sucrose 5.0%
0.6 M Sucrose 8.1%
0.8 M Sucrose 11.0%
1.0 M Sucrose 14.1%
% Change in Mass vs. Concentration of Sucrose
ooo,
140% +
12.0% +
10.0% 4
8.0% +
6.0% +
% Change in Mass
4.0% +
2.0% 4
0.0% +
0 02 04 06 08 10
62.0 $$
Concentration of Sucrose (Molarity)
* The interpretation of this exercise was that as the concentra-
tion of the solute increased, water will diffuse into the dialysis
bag (hypotonic to hypertonic), increasing the mass of the di-
alysis bag. An isotonic solution is evident with distilled water
176The 12 AP Biology Labs
(diffusion is happening at equal rates into and out of the di-
alysis bag).
Contents in Beaker Percent Change
0.0 M Distilled Water 19.0%
0.2 M Sucrose 8.0%
0.4 M Sucrose — 5.0%
0.6 M Sucrose —13.0%
0.8 M Sucrose -21.0%
1.0 M Sucrose -27.0%
Exercises 1C and 1D: Water Potential
% Change in Mass vs. Concentration of Sucrose
30.0%
% Change in Mass
Concentration of Sucrose (Molarity)
¢ The interpretation of this exercise indicates that when the line
crosses the x-axis at 0.36 M (estimation) that is the concentra-
tion when the potato core would be isotonic to the sucrose
concentration. A net change of 0% at x = 0.36 M is the con-
centration that the water potential in the potato tissue is equal
to the sucrose concentration (isotonic).
|177Chapter 38
* Calculation of water potential:
literbar
mmole
Wy sit = (0) (269) (ons | (295%) = 88 bars
If the calculated water potential is less than the water potential
surrounding the bag, water will flow into the bag (more solute
molecules inside the bag). If the calculated water potential is
greater than the water potential surrounding the bag, water
will flow out of the bag (less solute molecules inside the bag).
Thus, water will flow from a high to low water potential.
Exercise 1E: Onion Cell Plasmolysis
* Interpretation of this exercise:
> Onion cell in hypotonic solution will cause water to diffuse
into the cell, thus creating a turgid cell.
> Onion cell in hypertonic solution will cause water to dif-
fuse out of the cell, thus creating a plasmolyzed cell.
> Onion cell in isotonic solution will cause water to equally
diffuse across the cell. The cell will be flaccid.
Le) Pe see ry
Exercise 2A: Test of Catalase Activity
* Interpretation of this exercise:
>» The enzyme is catalase with the substrate being hydro-
gen peroxide (H,O,). The products released are water and
oxygen. Oxygen gas is flammable gas and will reignite a
glowing flint.
> Boiling catalase will denature the enzyme; therefore, the
enzyme will not function correctly.
178The 12 AP Biology Labs
Exercises 2B, 2C, and 2D: Enzyme Catalyzed Reaction
Time (seconds)
10 30 | 60 | 90 | 120 | 180 | 360
a) Base Line 36] 56] 56) S6| 56 | 5:6) 5:6
b) Final
Reading 10.1 | 14.4 | 15.6 | 15.8 | 15.8 | 15.8 | 15.8
©) Initial
Reading 7.1 | 12.3 | 14.2 | 15.0 | 15.7 | 15.7 | 15.7
d) Amount
of KMnO,
Consumed eee | Ce
e) Amount of
H,0, Used 26] 3.5) 42] 48] 5.5) 5.5] 5.5
Amount of H,O, Used vs. Time
a 6+
= cZ >
¥OF
é44
So
Hl
3
£ 1-H
°°}???
0 100 200 300, 400
Time (secs)
179Chapter 38
Lab 3 Mitosis and Meiosis
Exercise 3A.1: Observing Mitosis in Plant and Animal Cells
Using Prepared Slides of Onion Root Tip
and Whitefish Blastula
© The interpretation of this exercise:
> Visually be able to draw a cell in Interphase (non-dividing
portion of the cell cycle) and the 4 stages of mitosis.
Interphase
Prophase
Metaphase / \\Anaphase
Telophase
The 12 AP Biology Labs
/;
A
Exercise 3A.2: Time for Cell Replication
Number of Cells
Percent of | Time
Field | Field | Field Total Cells | in Each
1 ae 3 | Total | Counted Stage
Interphase | 500 | 600 |700 | 1800 82.0% 19 hr
41 min
Prophase 50 60 70 180 8.2% Thr
58 min
Metaphase | 30 40 50 120 5.5% Thr
30 min
Anaphase 15 20 30 65 3.0% 43 min
Telophase 8 10 12 30 1.3% 19 min
2195
|181Chapter 38
182
Anaphase, 3.0%
Metaphase, 5.596
Prophase, 8.2%
Telophase, 1.3%
Interphase, 82.0%
° The interpretation of this exercise:
>» The length of the cell cycle is roughly 24 hours with the
majority of that time spent in Interphase, getting prepared
for mitosis. Of the cells that one would observe in mitosis,
the predominant phase is prophase.
Exercise 3B.1: Meiosis
* The interpretation of this exercise:
> You must know the differences between meiosis and mitosis.
Number of Chromosomes
Number of DNA Replications
Number of Divisions
Number of Daughter Cells
Produced
Number of Chromosomes
Purpose/Function
Mitosis
2n-diploid
1
1
DB
2n-diploid
genetically
identical
Growth of
somatic cells
Meiosis
2n-diploid
il
2
4
n-haploid
genetically
variable
Generation
of gametesThe 12 AP Biology Labs
Exercise 3B.2: Crossing Over during Meiosis in
Sordaria fimicola
* The interpretation of this exercise:
>» The number of asci observed that show crossing over are
called recombinants. Recombinants are progeny that do
not resemble the genetic make-up of the parent.
> Sordaria fimicola is a fungus that after undergoing meio-
sis, another mitotic event will take place. This is unique to
many fungi including Saccharomyces cerevisiae or baker's
yeast.
» The crossing-over event that took place is depicted below.
The different combinations result in how the haploid cells
arranged themselves in the ascospore.
tan Meiosis Meiossit Mitosis
—_
— = 7.
+
ue — — , —
=
Number of
Number | Asci Showing
of 4:4 | Crossing Over % Asci
Sega See Total| Showing Gene
Asci | Crossing Over | Distance
156 165 318 | 156/318 =.49 | 24.5 map
0.49/2 = 24.5% units
183Chapter 38
WT ee
184
Exercise 4A: Plant Pigment Chromatography
* The interpretation of this exercise:
» The various plant pigments that help to run the photo-
synthetic machinery can be separated out based on solu-
bility in the solvent being used. The molecules involved
in this are chlorophyll a, chlorophyll b, carotenoids, and
xanthophylls, The relationship between the distance the
pigments travel in relation to the solvent is calculated by a
factor called R,.
R= distance pigment migrated
‘distance solvent front migrated
Band Number Distance (mm) Band Color
1 10 yellow green
2 23 blue green
3 33 yellow
4 49 deep yellow
5 105 yellow
Distance of solvent front 122 mm
105/122 = 0.86 | R, for carotene (yellow to yellow orange)
49/105 = 0.46 | R, for xanthophyll (yellow)
23/105 = 0.22 | R, for chlorophyll a (bright green to blue green)
10/105 = 0.095 | R, for chlorophyll b (yellow green to olive green)