GENERAL BIOLOGY 1 / MR.

REYMARK PLACAMBO SEM

BiOMOLECULES: CARBOHYDRATES & LiPiDS 01

[MODULE 1] BIOMOLECULES: CARBOHYDRATES AND LIPIDS

BIOMOLECULES GLYCOSIDIC BOND

• Major categories of Biomolecules • Linking bond: connects one (1) monosaccharide to another
o Carbohydrates because of the dehydration synthesis or the condensation
o Lipids reaction
o Proteins
o Nucleic Acid CARBOHYDRATES: FOOD SOURCE
• All biomolecules are composed of monomer and polymer • Simple carbs (simple sugars) are found in most candy and
o How are they formed? sweet drinks, fruits, vegetables, and milk. They are quick to
§ Dehydration Synthesis digest and give short burst of energy.
§ Hydrolysis Reaction • Complex carbs (like starches) are found in pasta, bread,
potatoes, legumes, and corn. They take longer to digest
Polymer Monomer and prove energy longer.
Carbohydrates Polysaccharides Monosaccharides
(Starch, (Glucose, LIPIDS
Glycogen, etc.) Fructose, etc.)
• All lipids are insoluble in water. Emulsifiers allow lipids to
Lipids Fats Triglycerides:
mix in water.
(Triglycerides, Glycerol and Fatty
• They are hydrophobic.
Oils, Waxes) Acids
• They have extremely diverse chemical structures.
Proteins Protein; Amino Acids
Polypeptides • They are classified to differences in structure and function
• Functions of Lipids:
Nucleic Acid DNA & RNA Nucleotides
o Fats – energy storage molecules, insulators
(GCAT and
against heat loss, and cushion tissue for organs.
GCAU)
o Oils – are generally something in our diet,
however they are converted to fats in our bodies
CARBOHYDRATES and therefore only function as a nutrient.
• Carbon, Hydrogen, and Oxygen: CnH2nOn o Phospholipids – main component of membranes.
• Source of energy o Steroids – hormones (messenger molecules) and
• The smallest carbohydrate is called monosaccharides, are components of cell membranes (cholesterol)
while the complex carbohydrate is polysaccharides
• All carbohydrates have approximately 2 hydrogen atoms TRIGLYCERIDES OR FATS
and 1 oxygen atom (e.g., water) for each carbon atom • Energy storage and insulations
hence the name ‘hydrates of carbon.’ • Cushioning of vital organs
• All formed from one glycerol molecule reacted with three
MONOSACCHARIDES fatty acid molecules through a condensation synthesis
• Building block of carbohydrates reaction.
• Major cellular nutrient • Made out of 2 basic units (building blocks):
• Often incorporated into more complex carbohydrates o Glycerol (alcohol) – is a three (3) carbon molecule
• Can be converted into other organic molecules that formed the backbone of triglyceride
• Example: Glucose, Galactose, Fructose o Fatty Acids – consists of three (3) long
• Mnemonics: GGF (Gives Good Flavor) hydrocarbon chains that divides these fats into two
groups:
DISACCHARIDES § Saturated Fatty Acid – no double bonds,
• Energy source solid (at room temp)
• Sweetener and dietary component § Unsaturated Fatty Acids – one or more
• Composed of two or monomers joined by a glycosidic bond double bonds, liquid (at room temp)
• Example: Lactose (galactose + glucose), Sucrose (glucose
+ fructose), Maltose (glucose + glucose) TYPES OF FATS IN OILS
• Mnemonics: LSM (Length Supports Movement) SATURATED MONOUNSATURATED
• Chain of carbon atoms • Chain of carbon atoms
POLYSACCHARIDES “saturated” with with one double bond
• Consist of hundreds of linked monosaccharides hydrogen • Liquid at room temp
• Complex carbohydrates • Solid at room temp • Lower melting point
• Storage and structural material • High melting point
• Example: Cellulose, Glycogen, Starch POLYUNSATURATED TRANS FATS
• Mnemonics: CGS (Can Get Stored) • Chain of carbon atoms • Partuoally hydrogenated
with multiple double (adding hydrogen
bonds causes trans fat to form)
• Liquid at room temp

K. HERRERA | 12 - COTTAM 1
 MODULE 1: BIOMOLECULES: CARBOHYDRATES AND LIPIDS

• Lowest melting point • Liquid oils industrially

converted into solids
• High melting points

PROPERTIES OF FATS AND OILS

• Oil – a mixture of triacylglycerols that is liquid because it
contains a high proportion of unsaturated fatty acids.
• Fat – a mixture of triacylglycerols that is solid because it
contains a high proportion of saturated fatty acids

PHOSPHOLIPIDS
• Major component of cell membranes. A cell membrane is
made up of two phospholipids;
o Polar head (hydrophilic) – organic molecule (e.g.
choline) and a phosphate group
o Non-polar tail (hydrophobic) – Diglyceride:
glycerol + 2 fatty acids
• The phosphate/Nitrogen group is charge and phospholipids
therefore have non-polar hydrophobic regions (fatty acids
and the glycerol) and polar hydrophilic regions (the
phosphate/nitrogen group).

STEROIDS
• Structure: four interconnected carbon rings. (ex. vitamin D,
cortisone, cholesterol)
• Steroids have two principal biological functions: as
important components of cell membranes which alter
membrane fluidity; and as signaling molecules.
• Base of sex hormones
• Emulsification of fats during digestion

CHOLESTEROL
• Good Cholesterol (High-Density Lipoprotein) – carries
cholesterol from other parts of your body back to your liver.
• Bad Cholesterol (Low-Density Lipoprotein) – transports
cholesterol from the liver to the tissues of the body.

HEALTH FACTS
• Saturated fats are associated with heart disease
• Fatty acids promote higher levels of blood cholesterol
• Animal fats also contain cholesterol, plants have no
cholesterol

K. HERRERA | 12 - COTTAM 2
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

BiOMOLECULES: PROTEiNS AND NUCLEiC 01

ACiDS; ENZYMES
[MODULE 2] BIOMOLECULES: PROTEINS AND NUCLEIC ACIDS; ENYZMES

PROTEINS • Phenylalanine • Proline

• Protein is an energy-yielding nutrient composed of carbon, • Threonine • Serine
hydrogen, oxygen, and nitrogen. • Tryptophan • Tyrosine
• Differs from carbohydrates and fats because of the • Valine
presence of nitrogen. • Lysine (usually, non-
• The body has at least 30,000 types of protein, each with a essential escept in
different job (many roles) times of illness and
• The building blocks of all protein molecules are amino stress)
acids In eukaryotes, there are only 21 proteinogenic amino acids, the
• Complex structure 20 of the standard genetic code, plus selenocysteine.
• Energy Source
DISTRIBUTION OF PROTEINS IN THE BODY
AMINO ACID • Muscle
• Possess carboxyl and amino groups • Bone
• Differ in their properties due to differing side chains (R • Skin
Groups) • Other: blood, glands, nerve, tissue

HOW ARE THESE AMINO ACIDS LINKED? PROTEIN FUNCTIONS

• A peptide bond is a chemical bond formed between two • Enzymatic (rubisco)
molecules when the carboxyl group of one molecule reacts • Storage (ferritin)
with the amino group of the other molecule, releasing a • Structural (spider silk)
molecule of water (H2O) • Protection (immunoglobulin)
• This is a dehydration synthesis reaction (also known as a • Hormonal (insulin)
condensation reaction), and usually occurs between amino • Contractile (actin)
acids. • Receptor (rhodopsin)
• Two linked amino acids forms a dipeptide, three forms a • Transport (hemoglobin)
tripeptide, and long chains of amino acids are polypeptide
STRUCTURAL ROLES
FOUR LEVELS OF PROTEIN STRUCTURE
• Keratin
• Primary Structure - Amino acid sequence o Makes up hair and nails
• Secondary Structure - Hydrogen bonding • Collagen
• Tertiary Structure - Side chain interactions o Supports in ligaments, tendons, and skin
• Quaternary Structure - 2 of more polypeptides • Actin and Myosin
o Make up muscle fibers in muscle cells that allow
AMINO ACIDS CAN BE CLASSIFIED IN TWO WAYS: contraction and are major component of the
• Essential Amino Acids cytoskeleton of cells.
o There are 21 amino acids that are required for • Histones
building proteins in our bodies. o Protein associated with DNA to make
§ Essential/Indispensable amino acids chromosomes.
must be ingested since our bodies do not • Intercellular Filaments
manufacture these molecules o Hold cells together.
§ 9 amino acids that come from the diet
• Non-Essential Amino Acids HORMONAL ROLES
o Non-essential/dispensable amino acids can be • Insulin
made by our bodies from other amino acids. o Messenger molecule in blood from pancreas that
§ Your body can synthesize 11 of the signals for cells to absorb glucose.
amino acids from the other amino acids • Cyclin
o Messenger molecule in blood to signal cells to go
Conditionally into stages of mitosis
Essential Non-Essential
Non-Essential
• Histidine • Arganine • Alanine TRANSPORTATION ROLES
• Isoleucine • Asparagine • Asparatate
• Hemoglobin
• Leucine • Glutamine • Cysteine o Transports oxygen to the blood
• Methionine • Glycine • Glutamine

K. HERRERA | 12 - COTTAM 1
 MODULE 2: BIOMOLECULES: PROTEINS AND NUCLEIC ACIDS; ENZYMES

DENATURATION THERE ARE FIVE NITROGENEOUS BASES IN TOTAL

• The protein we consume can be altered and changed but
can never return to its initial form. This is called
denaturation.
• Factors that cause denaturation:
o Heat
o Acids
o Bases
o Alcohol

NUCLEIC ACIDS
• Store and transmit hereditary/genetic information POLYNUCLEOTIDE
• Nucleic acid is a polymer consisting of monomers called the • Unique sequence of nucleotides
nucleotides and polynucleotides • Types:
• Are large organic molecules that carry the “code of life” o Deoxyribonucleic Acid (DNA)
• 2 main types of nucleic acids: o Ribonucleic Acid (RNA)
o Deoxyribonucleic acid (DNA) – double helix
o Ribonucleic acid (RNA) – single helix DEOXYRIBONUCLEIC ACID
• Stores information for the synthesis of specific proteins
NUCLEOSIDE • Directs rRNA synthesis
• The substructure composed of nucleobase plus sugar; • Deoxyribose
without phosphate • A, T, C, G
• 4 N-containing bases found in DNA:
• Forms a double helix
o Guanine
o Cytosine
o Adenine
o Thymine
• For RNA, thymine is replaced with Uracil

NUCLEOTIDE
• Consists of: RIBONUCLEIC ACID
o Pentose sugar
• Essential in coding, decoding, expression, and regulation of
o Nitrogenous base
genes
o Phosphate group
• Single chain
• A, C, G, U

K. HERRERA | 12 - COTTAM 2
 MODULE 2: BIOMOLECULES: PROTEINS AND NUCLEIC ACIDS; ENZYMES

MELTING AND RE-ANNEALING MECHANISM

• High temperature and/or low salt concentration causes the • In most instances, only one small part of the enzymes,
two strands to melt or disassociate. called the active site, associates directly with the substrate
o Hybridization: in a mixture of DNA with different (s).
sequences, the complementary strands will find
each other in the mixture. METABOLIC PATHWAY
• A series of linked reactions
• Begin with a particular reactant and end with a final product.

SUBSTRATE BINDING
• Binding a substrate induces the conformational changes in
enzyme molecule (induced fit model)
• An enzyme-substrate (ES) complex is formed

LOCK AND KEY MODEL

• The lock and key model of enzyme action, proposed earlier
JAMES WATSON & FRANCIS CRICK this century, proposed that the substrate was simply drawn
• Describes DNA as a double helical structure into a closely matching cleft on the enzyme molecule.
ENZYMES AND FACTOR AFFECTING ITS ACTIVITY

ENZYMES
• It increases the speed of chemical reactions without being
consumed by the reaction.
o Not all enzymes are proteins.
§ Ex. Ribozymes – made of RNA

INDUCED FIT MODEL

• The induced fit model is the configurations of both the
enzyme and substrate are modified by substrate binding.
• This model proposes that the initial interaction between
enzyme and substrate is relatively weak, but that these
weak interactions rapidly induce conformational changes in
the enzyme that strengthen binding.

STRUCTURE OF ENZYMES
• Enzyme Structure
o Proteins that work as catalyst
o Speed up chemical reactions without being altered
themselves.

ENERGY OF ACTIVATION (EA)

• The energy that must be added to cause molecules to react
with one another

K. HERRERA | 12 - COTTAM 3
 MODULE 2: BIOMOLECULES: PROTEINS AND NUCLEIC ACIDS; ENZYMES

SUMMARY OF CARBOHYDRATES, NUCLEIC ACIDS,

LIPIDS, AND PROTEINS
FACTORS AFFECTING ENZYME ACTIVITY
• Substrate Concentration
o Enzyme activity increases as substrate
concentration increases.
• Optimal pH
o Each enzyme has an optimal pH at which the
reaction rate is highest
• Temperature
o As temperature rises, enzyme activity increases
o Denaturation

EXCEPTIONS
• Environmental influence
• Bacteria living in hot springs have enzymes that withstand
high temperatures
• Enzyme inhibition
o Occurs when a molecule (the inhibitor) binds to an
enzyme and decreases its activity.

• Noncompetitive inhibition
o The inhibitor binds to the enzyme at a location
other than the active site known as the allosteric
site, thus changing its shape and its function.

• Competitive inhibition
o Occurs when an inhibitor and the substrate
compete for the active site of an enzyme.

K. HERRERA | 12 - COTTAM 4
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

CELLS 01
[MODULE 3] CELL THEORY, STRUCTURES AND FUNCTIONS, AND PROKA VS. EUKA

CELL
• The cell is the smallest unit of matter that can carry on the • 1831
processes of life. o Robert Brown
o “All living things are made of cells.”
CELL SHAPE • 1838
• Cells come in variety of shapes depending on their o Matthias Schleiden and Theodor Schwann
functions. o Plant Cell and Animal Cell
• Example: o “Cells are the basic unit of life.”
o Neuron – long and thin • 1858
o Blood Cells – rounded disks o Rudolph Virchow
o “All cells come from pre-existing cells.”
CELL SIZE
• Few cells are large enough to be seen by the unaided eye. THE CELL THEORY
• Most cells can only be seen by the aid of a microscope • All living things or organisms are made of cells
• Cells are the basic building units of life
INTERNAL ORGANIZATION • New cells are created by old cells dividing into two
• Cells contain a variety of internal structures called
organelles EXCEPTIONS
• Viruses
BASIC CELL PARTS AND THEIR FUNCTIONS • Mitochondria
• Cell Membrane • Chloroplast
o Outer layer of the cell
o Selectively permeable TYPES OF CELLS AND THEIR FUNCTIONS
o Composed of double layer phospholipids in which (PROKARYOTES VS EUKOARYOTES)
proteins are embedded • Cells are divided into two types:
o Physically separates the intracellular space and o Prokaryote
the external environment of the cell o Eukaryote
o Surrounds and protects the cytoplasm • Phylogenetic and symbiogenetic tree of living organisms,
• Cytoplasm showing a view of the origins of eukaryotes & prokaryotes.
o Enclosed by the cell membrane
o The cytosol is the fluid portion of the cytoplasm PROKARYOTIC CELLS
o It has three (3) components:
• Single compartment enclosed by a cell membrane
§ The cytoskeleton
• Lacks nucleus
§ Organelles
§ Cytoplasmic inclusions and dissolved • No membrane-bound organelles
solutes • Two main groups:
• Genetic Material o Archaea
o Referred as the DNA (Deoxyribonucleic Acid) o Bacteria
o DNA is found in the NUCLEUS of EUKARYOTIC
cells (animals and plants) and in the CYTOPLASM BACTERIAL CELL
of PROKARYOTIC cells (bacteria) that determines • Flagellum (only in some types of prokaryotes)
the composition of an organism. o Long, whip-like protrusion that aids cellular
• Ribosome locomotion.
o Structures that manufacture proteins (synthesizes • Capsule (only in some type of prokaryotes)
protein o Adds protection or enables the cell to attach to
surfaces.
CELL THEORY • Cell Wall (except genera Mycoplasma and Thermoplasma)
• 1665 o Outer covering of most cells that protects the
o Robert Hooke bacterial cell and gives it shape.
o Coarse compound microscope • Cell Membrane
o Very thin slices of cork o Surrounds the cell's cytoplasm and regulates the
o Hooke called them cells. His description of these flow of substances in and out of the cell.
cells where published in Micrographia • Cytoplasm
• 1674 o A gel-like substance composed mainly of water
o Anton van Leeuwenhoek that also contains enzymes, salts, cell
o Animalcules components, and various organic molecules.
o He also described the algae Spirogyra • Ribosome
o Cell structure responsible for protein production.

K. HERRERA | 12 - COTTAM 1
 MODULE 3: CELL THEORY, STRUCTURES AND FUNCTIONS, AND PROKA VS. EUKA

• Nucleoid o Functions: Responsible for digestion of nutrients,

o Area of the cytoplasm that contains the bacteria and damaged cells
prokaryote's single DNA molecule
• Pili
o Serves as an attachment of bacterial cells to other • Peroxisome
cells o Characteristics: Spherical membranous vesicles
that contain enzymes
ARCHAEAN CELLS o Function: Detoxify harmful molecules and the
enzymes produced are involved in the oxidative
• Resembles bacterial cells in some ways. Like bacteria, they
deamination of amino acids and breakdown of
are smaller and lacks nucleus and are also one celled
hydrogen peroxide.
organism.
• Vacuoles
o Characteristics: Membranous sac
EUKARYOTES CELLS
o Function: Store and release various substances
• One of the two major cell types within the cytoplasm, responsible for cell
• Has nucleus and membrane-bound organelles enlargement and water balance
• Both animals and plants have eukaryotic cells. • Cytoskeleton:
o Characteristics: Dense network of protein fibers
PARTS o Function: Provides a framework that supports the
• Cell Membrane shape of the cell and anchors organelles
o Characteristic: The outer layer of a cell o Elements:
o Function: Regulates the entrance and exit of § Microfilaments – responsible for cellular
substances in the cell movements such as contraction,
• Cytoplasm pinching during division, and formation
o Characteristics: A jelly-like substance which is for cellular extensions
composed of water with dissolved substances § Microtubules – responsible for the
o Functions: Responsible for the fluid nature of the movement of chromosomes in mitosis
cell’s internal environment and allows the § Microtubules – responsible for the
organelles to suspend dynamically. movement of chromosomes in mitosis
• Ribosomes • Cell Wall
o Characteristics: Occur as free particles suspended o Characteristics: The outermost layer of plant cells
within the cytoplasm or attached to the that contains cellulose
membranous wall of the ER o Function: Provides support to the plant’s body
o Functions: Synthesizes protein molecules • Nucleus
• Endoplasmic Reticulum o Characteristics: Bounded by a membrane
o Characteristics: Series of membranous channels o Function: Controls or regulates all chemical
that forms a continuous network extending from reactions within the cell
the cell membrane to the nucleus
o Function:
§ Rough ER – associated with active
protein synthesis process
§ Smooth ER – no ribosomes; involved in
the synthesis and transport of lipids
• Golgi Apparatus
o Characteristics: Cluster of flattened membranous
sacs that are continuous with the channels of
smooth ER
o Function:
§ For storage, modification and packing of
materials produced for secretory export
§ Involved in the formation of lysosomes
and other transport vesicles of the cell Lecture Video / Source:
Part 1: https://www.youtube.com/watch?v=kpaqTm1BTL0
• Mitochondria
Part 2: https://www.youtube.com/watch?v=mCTw8bRCFDM
o Characteristics: Double walled membranous sacs
with folded inner partitions called cristae
o Function: Release energy from food molecules
and transforms it into usable ATP
• Chloroplast
o Characteristics: Double membrane organelles
with inner flattened sacs called thylakoids
o Function: Responsible for the conversion of light
energy into chemical energy of sugars during
photosynthesis
• Lysosome:
o Characteristics: Single walled membranous sacs.

K. HERRERA | 12 - COTTAM 2
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

ANiMAL AND PLANT CELLS 01

[MODULE 4-5] ANIMAL AND PLANT CELLS

TISSUES o Cuboidal
• Tissues is a combination of similar cells that work together § Cube-shaped cells
to perform a particular function. § Absorb nutrients; produce secretions
o Columnar
CATEGORIES OF ANIMAL TISSUES § Tall and thin
§ Absorb nutrients; produce secretions
NERVOUS TISSUE
• Nervous Tissues uses electrical signals to convey LAYERING
information rapidly within an animal’s body. • Simple – one layer
• Neuron (First Main Cell Type) • Stratified – two or more layers
o Forms communication networks that receive, • Pseudostratified – mostly just one layer, cells with different
process, and transmit information. shapes and sizes
o Neuron is made up of:
§ Dendrites – transmit information toward NAMING EPITHELIAL TISSUES
the cell body. • Tissue’s first name as its number of layers, and its last
§ Cell Body – contains the nucleus, name as the shape of its cells
mitochondria, ribosomes and other
organelles. Example:
§ Axon – conducts nerve impulses away
• Simple Squamous Epithelium – single layer, flat, scale-
from the cell body.
like cells
• Neuroglial/Glial Cells (Second Main Cell Type)
• Stratified Squamous Epithelium – multiple layer, flat
o Supports the neurons and assist in their
shaped cells
functioning.
• Stratified Cuboidal Epithelium – multiple layers, cube
shaped
MUSCLE TISSUE
• This consists of cells that contract when electrically
Usual locations:
stimulated.
Simple Squamous Stratified Squamous
• It allows the movement of other tissues and organs.
• Animal bodies have three types of muscle tissues: • Air sacs of the lungs • Skin
• Lining of blood vessels, • Vagina
SKELETAL MUSCLE TISSUE heart and lymphatic • Esophagus
• Long multinucleate parallel cells; striations (fine black lines tubes • Mouth
running perpendicular to the fibers); voluntary Cubodial Simple Columnar
• Occur in muscles which are attached to the skeleton.
• Line the digestive tract,
CARDIAC MUSCLE TISSUE • Kidney tubules gallbladder and
• Duct and small glands excretory ducts of some
• Striated; involuntary; cells divided and converge, one
• Surface of ovary glands. Has microvilli at
nucleus per cell, with intercalated discs. surface for absorption.
• Occurs only in the heart.
Pseudostratified Ciliated Columnar
SMOOTH MUSCLE TISSUE • Lines the bronchi, trachea, uterine tubes and some of
• Short tapered cells; no striations involuntary the uterus. Propels mucus or reproductive cells by
• Located in walls of hollow visceral organs, except the heart. ciliary action

EPITHELIAL TISSUE CONNECTIVE TISSUE

• Epithelial Tissue is the shape of the individual cells and the • The most widespread tissue in the vertebrate’s body is the
number of layers they form Connective Tissue. It consists of cells that are embedded
within the extra cellular matrix rather than being attached to
CELL’S SHAPE one another.
• The shape of each kind of epithelial cell correlates with its • Connective Tissue fills the spaces attach epithelium to
function. other tissues, protect and question organs, and provide
o Squamous both flexible and firm structural support.
§ Flattened cells or fish scale, thin
§ Fast absorption and diffusion, making LOOSE CONNECTIVE TISSUE
thin membranes • Composition: Cells in loose matrix of elastin and collagen
fibers.

K. HERRERA | 12 - COTTAM 1
 MODULE 4-5: ANIMAL AND PLANT CELLS

• Functions: Holds organs in place; attaches epithelial tissue o Lateral Meristem

to underlying tissue. § In addition to the apical meristems
• Location: Under skin, between organs located in the shoot and root tups, plants
in the DICOT class have lateral
DENSE CONNECTIVE TISSUE meristems.
§ Lateral meristem cause secondary
• Composition: Cells in dense matric of elastin and collagen
growth
fibers
§ Secondary growth causes stems and
• Functions: Connects muscle to bone (tendons); connects roots to grow larger in diameter
bone to bone (ligaments) § Also known as cambium
• Location: Tendons and ligaments • Vascular Cambium – located
between the xylem and phloem
ADIPOSE TISSUE and gives rise to secondary
• Composition: Fat cells in minimal matrix xylem and phloem.
• Functions: Stores fat for energy and insulation • Cork Cambium – located
• Location: Beneath the skin, between muscles, around heart outside the phloem and gives
and joints rise to the cork which consists of
suberized cells.
BLOOD o Intercalary Meristem
§ Occurs between mature tissue sections
• Composition: Red blood cells, white blood cells, platelets in
near the stem internodes or leaf
plasma matrix
attachments
• Functions: Transport gases, nutrients, wastes hormones
§ Can be found only in monocotyledons
• Location: In arteries, veins, and capillaries
APICAL INTERCALARY LATERAL
CARTILAGE MERISTEM MERISTEM MERISTEM
• Composition: Cells in matrix of fine collagen fibers The area of The area of
• Functions: Flexible support actively dividing The area of actively dividing
• Location: Ears, joints, bone ends, respiratory tract cells that locates actively dividing cells that locates
at the tips of the cells that locates at the lateral side
BONE roots and the at the internodes. of the stem and
shoots. the root.
• Composition: Cells in matrix of collagen and minerals
POSITION
• Functions: Firm support
• Location: Skeleton Internodes or at Lateral surface of
Tips of root and
the base of the the stem and the
shoot.
leaves. root.
Summary: FUNCTIONAL ROLE
• Epithelial tissue – Covers interior and exterior surfaces Aids increase of Increases the
of organs. It is also for protection, secretion, and height of the plant Contributes to the thickness of the
absorption. by facilitating the increase in height, plant by
• Connective Tissue – Gives support, adhesion, growth of the with the growth of increasing the
insulation, attachment, and transportation. shoot and the the internodes. diameter of the
• Muscle Tissue – For movement root. plant.
• Nervous Tissue – For rapid communication among cells

PLANT TISSUES PERMANENT TISSUES

• Are formed by the differentiation of meristematic cells,
MERISTEMATIC TISSUE which become specialized to perform specific functions like
protection, support, storage, and transport of food and
• Is composed of a small population of meristematic cells
water.
which grow and divide to produce new cells, but never
mature themselves. • There are three types of Permanent Tissues
o Dermal Tissues
• Characteristics:
§ Consists of the Epidermis and Periderm
o Small size
o Very thin primary wall • Epidermis
o No central vacuole o Is a single layer of
o Dense cytoplasm closely packed cells
o The nucleus occupies a large part of the cell o Stoma, trichomes, and
root hairs
• Main Types of Meristem:
o Apical Meristem • Periderm
§ Occur at the tips of the roots and shoots o Also called as bark
§ Responsible for the extension in length of which replaces the
the plant body (primary growth) epidermis in plants
that undergo
secondary growth.

K. HERRERA | 12 - COTTAM 2
 MODULE 4-5: ANIMAL AND PLANT CELLS

o Ground Tissues
§ Comprise of Parenchyma, Collenchyma,
and Sclerenchyma
• Parenchyma
o Are usually described
as typical plant cells
because they are not
very specialized.
• Collenchyma
o Bears a strong
resemblance to
parenchyma cells.
• Sclerenchyma
o They have thick
secondary walls
usually strengthened
by lignin and are much
more rigid.
o Vascular Tissues
§ Includes the Xylem and Phloem
• Phloem
o Which transports
dissolved nutrients in
all directions within the
plant (PMF).
o Phloem Fibre,
Companion Cells,
Phloem Parenchyma,
Sieve Tubes
• Xylem
o Which conducts water
and minerals from
roots upward and
throughout the plant
(XUW).
o Xylem Parenchyma,
Xylem Fibre, Vessel,
and Tracheids

Lecture Video / Source:

Nervous and Muscle Tissues:

https://www.youtube.com/watch?v=mxBq2d5eS54
Epithelial Tissue:
https://www.youtube.com/watch?v=uqqapB1tcz0
Connective Tissue:
https://www.youtube.com/watch?v=xbyhSDb5fgk
Meristematic Tissues:
https://www.youtube.com/watch?v=3zgbQRGqgS8
Permanent Tissues:
https://www.youtube.com/watch?v=yQbZGru4gBU

K. HERRERA | 12 - COTTAM 3
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

TRANSPORT MECHANiSMS 01
[MODULE 6] TRANSPORT MECHSANISM

CELL MEMBRANE • Isotonic – the cell’s interior is normally isotonic to the

• A phospholipid bilayer studded with proteins surrounding blood plasma. Water enters and leaves the cell
at the same rate and the cell maintains its shape.
TYPES OF TRANSPORT MECHANISM • Hypotonic – when the salt concentration of the plasma
decreases, water flows into the cell faster than it leaves.
PASSIVE TRANSPORT The cell swells and may even burst.
• Does not require energy input • Hypertonic – where in the salty surroundings, the cell loses
• In passive transport, a substance can move across a water and shrinks or shrivels and may die for lack of water.
membrane without the direct expenditure of energy.
• All forms of passive transport involves diffusion

DIFFUSION
• The spontaneous movement of a substance from a region
where it is more concentrated to a region where it is less
concentrated.
• Diffusion is the natural tendency for molecules to move of
potential energy constantly.

SIMPLE DIFFUSION
• A substance moves down its concentration gradient without
the use of transport protein.
• Substances may enter or leave cells by simple diffusion
only if they pass freely through the membrane.
• Two solutions of different concentrations may be separated OSMOSIS OF PLANT CELL
by a selectively permeable membrane through which water • Isotonic – where it shows the normal cell, the cell is flaccid
but not solutes can pass. In that case, water will diffuse • Hypotonic – the interior of a plant cell usually contains more
down its concentration gradient toward the side with a high concentrated solute than its surroundings. Water enter the
solute concentration. cell by osmosis generating turgor pressure. Turgor
pressure helps keep plants erect.
OSMOSIS • Hypertonic – the turgor pressure is low, therefore, the plant
• Is the simple diffusion of water across a selectively wilts.
permeable membrane.
FACILITATED DIFUSSION
TONICITY • A form of passive transport in which a membrane protein
• Is the ability of a solution to cause water movement assists the movement of a polar solute along its
o Isotonic – equal (it is a condition in which solution concentration gradient.
concentration is the same on both side of the semi- • Ions and polar molecules cannot freely pass or cross the
permeable membrane) hydrophobic later membrane, instead, transport proteins
o Hypotonic – under (a solution in which the solute form channels that help these cross.
concentration is less than on the other side of the • Facilitated diffusion releases energy because the solute
semi-permeable membrane) moves from where it is more concentrated to where it is less
o Hypertonic – over (the solution concentration is concentrated.
greater than on the other side of a semi-permeable
membrane) ACTIVE TRANSPORT
• A cell uses a transport protein to move a substance against
OSMOSIS IN RED BLOOD CELLS its concentration gradient from where it is less concentrated
to where it is more concentrated.
• Because a gradient represents a form of potential energy,
the cell must expend energy to create it. This energy often
comes from ATP, therefore, active transport requires
energy input.

SODIUM-POTASSIUM PUMP
• Active transport system in the membranes of most animal
cell.
• Uses ATP as an energy source to expel 3 Na+ for every 2
K+ it admits.

K. HERRERA | 12 - COTTAM 1
 MODULE 6: TRANSPORT MECHANISM

• It uses energy release in ATP hydrolysis to move potassium

ions into the cell and sodium ions out of the cell. The
process caused energy because both types of ions are
moving from where it is less concentrated to where they are
more concentrated.

TRANSPORT USING VESICLES

• Most molecules dissolve in water are small. They can cross
the cell membrane by simple diffusion, facilitated diffusion,
or active transport. Large particles, however, must enter
and leave cells with the help of transport vesicles.
• A vesicle is a small sac that can pinch off of or fuse with a
cell membrane

ENDOCYTOSIS
• A cell membrane engulfs fluids and large molecules to bring
them into the cell.
• When the cell membrane indents, a bubble of membrane
closes in on itself. The resulting vesicle traps incoming
substance. The formation and movement of this vesicle
requires energy.
• Types of Endocytosis:
o Pinocytosis
§ The substance engulfed is liquid (the cell
involves small amounts of fluids and
dissolves substances)
§ “Cell drinking”
o Phagocytosis
§ The substance engulfed is solid
§ “Cell eating”

EXOCYTOSIS
• The opposite of endocytosis, uses vesicles to transport
fluids and large particles out of the cells.
• Inside the cell, the Golgi apparatus produces vesicles filled
with substances to be secreted. The vesicle moves to the
cell membrane and joins with it releasing the substance out
of the cell.

Lecture Video / Source:

Passive Transport:
https://www.youtube.com/watch?v=JClLadVCi60
Active and Transport with Vesicles:
https://www.youtube.com/watch?v=ITo54aFHl-Q

K. HERRERA | 12 - COTTAM 2
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

MiTOSiS 01
[MODULE 7] MITOSIS

THE CELL CYCLE • Organelles replicate

SYNTHESIS (S) STAGE

• DNA replication takes place
• The amount of DNA per cell doubles
• There is no increase in chromosome number

CELL DIVISION

MITOSIS
• Occurs in somatic cells (cells that make up everything in our
body except sex cells. example: skin, bones, blood, etc.)
• Forms body cells
• The parent cell splits into two (2) daughter cells
• Daughter cells are identical

MEIOSIS
• Occurs in gamete-producing cells (eggs cells for females
and sperm cells for males)
• Forms gametes

Count the
number of
chromosomes
based on the
number of
centromeres!

GAP 2 (G2) STAG

• Proteins are synthesized in preparation for mitosis
INTERPHASE • Cell growth continues
• 95% of the cell cycle
QUIESCENT (G0) STAGE
GAP 1 (G1) STAGE • Inactive Stage/resting phase
• The cell is metabolically active and continuously grows but • Metabolically active but no longer proliferate unless called
does not replicate its DNA on to do so

K. HERRERA | 12 - COTTAM 1
 MODULE 7: MITOSIS

MITOSIS CYTOKINESIS: ANIMALS

• Also called as equational division (because the • Formation of Cleavage Furrow
chromosomes are equally distributed to the daughter cells.
the daughter cells are what are produced after mitosis or
cell division. This means that the daughter cells produced
after mitosis have the same amount of genetic materials.
Also the chromosome number of the cells the daughter cells
is the same with the chromosomes number of the parent
cell.)

PROPHASE (P)
• The chromatin starts to condense or become thicker. (they
become chromosomes visible under the microscope)
• The nuclear envelope (or nuclear membrane) starts to
disappear. CYTOKINESIS: PLANTS
• The centrioles have moved to the opposite poles. Assembly • Formation of Cell Plate
of spindle fibers (which are made up of microtubules which
is one of the cytoskeleton components of the cell) is visible.
Spindle fibers start attach to the kinetochores of the
chromosomes.

METAPHASE (M)
• Chromosomes line up at the metaphase/mitotic plate.
Spindle fibers have completely attached to the kinetochores
of all chromosomes.
• Each chromatid now has an attached spindle fiber in their
kinetochore.

ANAPHASE (A) Lesson Video / Source:

• The centromeres split and the chromatids move to the
opposite poles (toward centrioles). Interphase: https://youtu.be/9B73DN7a5a4
• From sister chromatids, they split into individual chromatids. Mitosis: https://www.youtube.com/watch?v=I2r-uIwFEgc
These individual chromatids are going to be pulled away
from each other by the spindle fibers with the help of
centrioles to the opposite poles of the cell.

TELOPHASE (T)
• The chromosomes cluster at the opposite poles. After this,
nuclear envelope will re-appear and the chromosomes start
to decondense.

Example (micrographs of onion cell undergoing mitosis):

K. HERRERA | 12 - COTTAM 2
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

MEiOSiS 01
[MODULE 8] MEIOSIS

Review: o Synaptonemal complex disintegrates

o Chiasma is still present
CELL DIVISION • Diakinesis
o Chromosomes are now fully condensed
MITOSIS o Assembly of meiotic spindle fibers
• Occurs in somatic cells (cells that make up everything in our o The nuclear envelope disappears
body except sex cells. example: skin, bones, blood, etc.)
• Forms body cells METAPHASE I
• The parent cell splits into two (2) daughter cells • Bivalents align on the equatorial plate
• Daughter cells are identical • Microtubules from the opposite poles attach to the pair of
homologous chromosomes
MEIOSIS • Random assortment
• Occurs in gamete-producing cells (eggs cells for • Number of possible arrangement = 2n
females and sperm cells for males) • n = # of chromosomes in haploid set
• Forms gametes Example: The dividing cell is the human spermatogonium, which
means it has 46 chromosomes. If the cell is in Metaphase I, how
many possible arrangements of the chromosomes will there be?

Possible arrangements = 2n
N = # of chromosomes in a haploid test

Possible arrangements = 223

Possible arrangements = 8,368,608

ANAPHASE I
• The homologous chromosomes separate
• Sister chromatids remain associated at their centromeres

TELOPHASE I
• Nuclear membrane reappears
INTERPHASE
• Growth 1 CYTOKINESIS
o Cell becomes larger
o Organelles duplicate
• Synthesis
o Genetic materials (DNA) duplicate
o Number of chromosomes stays the same
• Growth 2
o Cells continues to grow
o Enzymes are produced

MEIOSIS I

PROPHASE 1
• Leptotene
o Compaction of chromosomes
• Zygotene
INTERKINESIS
o Pairing of homologous chromosomes (synapsis)
o Homologous chromosomes are linked by • The period of rest that cells of some species enter during
synaptonemal complex meiosis between Meiosis I and Meiosis II
o Formation of bivalent/tetrad
• Pachytene MEIOSIS II
o Crossing-over takes place
o Crossing-over – exchange of genetic materials PROPHASE II
from non-sister chromatids • Nuclear membrane breaks down
o Formation of chiasma (chiasmata) • Chromosomes compact
• Diplotene
o Homologous chromosomes migrate apart

K. HERRERA | 12 - COTTAM 1
 MODULE 8: MEIOSIS

METAPHASE II
• Chromosomes align at the equator
• Microtubules attach to the sister chromatids

ANAPHASE II
• Splitting of centromere
• Movement of sister chromatids towards opposite poles

TELOPHASE II
• Nuclear envelope reappears

CYTOKINESIS
• Wherein we get four haploid cells which are now called as
the sex cells or the gametes (sperm cell for males and egg
cells for females)
• These four daughter cells are different from each other and
from their parents cells. this means that each daughter cells
or gametes represents one unique outcomes out of millions
of possible outcomes.
• For humans, these daughter cells have 23 chromosomes
each, where in a sex cells needs to combine with another
sex cell to make a cell with 46 chromosomes.

CHROMOSOMAL ABERRATIONS
• Down Syndrome (Trisomy 21)
• Klinefelter’s Syndrome
• Edward’s Syndrome
• Rett Syndrome

Lesson Activities / Sources:

Interphase: https://www.youtube.com/watch?v=eFmGw6iHtvI
Meiosis I: https://www.youtube.com/watch?v=W_R79-ZEewA
Meiosis II: https://youtu.be/lrp4HRTz144
Chromosomal Aberrations:
https://www.youtube.com/watch?v=zQZl86wsId4

K. HERRERA | 12 - COTTAM 2
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

PHOTOSYNTHESiS 01
[MODULE 9] PHOTOSYNTHESIS

PHOTOSYNTHESIS REDUCTION-OXYDATION REACTION

• The process of converting light energy to chemical energy • A type of chemical reaction that involves transfer of
of food. electrons
• The process needs carbon dioxide and water and with the o Oxidation: Loss of electrons
help of the light energy coming from the sunlight, it o Reduction: Gain of electrons
produces sugars or carbohydrates in the form of sucrose • Photosynthesis happens in a series of reactions and these
or starch and there is also a release of the by-product called reactions are called as the redox reactions from the word
as the oxygen. reduction in oxidation.
• Photosynthesis occurs in the leaves of the plants • When a molecule is removed with an electron, another
specifically in the mesophyll cells of the leaves. And this molecule has to accept the removed electron and the
happens in the palisade and the spongy parenchyma of the process of removing an electron from a molecule is called
leaves. as oxidation while the process of gaining or receiving the
• Photosynthesis is regulated by the small openings found on removed electron is called as the reduction.
the underside of the leaves which are called the stomata. • Mnemonics:
o Leo-Ger
STOMATA § Loss of Electron-Oxidation
• Are pores in a plant’s cuticle through which water vapor and § Gain of Electrons-Reduction
gases (CO2 and O2) are exchanged between the plant and
the atmosphere. Important Terms to Remember:
• Found in the underside of the leaves.
• The closing and opening of a stoma is regulated by the two • ADP – Adenosine diphosphate (two phosphate groups)
guard cells. • ATP – Adenosine triposphate (three phosphate groups)
(this molecule that the cells of the body use for their
metabolic processes / energy currency of living
organisms)
• NADP – Nicotinamide adenine dinucleotide
• NADPH – Nicotinamide adenine dinucleotide phosphate

2 STAGES OF PHOTSYNTHESIS

PHOTO
(A) LIGHT REACTIONS
• Also called as the photochemical reactions
• Convert light energy to chemical energy
• Occur in the thylakoid (thylakoid membrane)
• Produce 02, ATP, and NADPH
CHLOROPLAST
• Specifically, photosynthesis happen and is found only in • Light is a form of electromagnetic energy, which travels in
plants and other photosynthesizing organisms. And these waves.
organelles are found in the mesophyll cells of the leaves. • Light is composed of packets of energy called photons. The
These organelles are called as the chloroplast. energy of these can be categorized based on the region
• Chloroplast has the following parts: energy that they contain. Radiation can be quantified based
on the wavelength which is the distance between the two
successive peaks which are called as the throw.

K. HERRERA | 12 - COTTAM 1
 MODULE 9: PHOTOSYNTHESIS

• The electromagnetic is plotted in a straight line starting from Photosystem I Photosystem II

the most having the longest wavelength which becomes Reaction center: p700 Reaction center: p680
shorter toward the right. As the wavelength shortens or Primary acceptor: Primary acceptor:
decreases, the energy becomes stronger. Hence, the Chlorophyll Ao Pheophytin
strongest wave is the gamma rays. More chl a than chl b More chl b than chl a
• On the other hand, there is a special very small portion in Cyclic and Non-cyclic Non-cyclic electron flow
the wavelength which is called as the visible spectrum. This electron flow
visible spectrum contains just the right amount of energy
that plants need to perform photosynthesis. It ranges from NON-CYCLIC ELECTRON FLOW
380 nanometers to 740 nanometers. The colors of this light
in this spectrum Is visible to the human eye, hence the • Primary pathway of energy transformation in the light
name. reactions
• Involves photosystem I and II, photosynthetic electron
• Pigments are substances that absorb visible light. transport chain, and ATP synthase
• Produces O2,ATP,andNADPH
Chlorophylls Carotenoids
Step 1: Pigment molecule in photosystem II absorbs a photon of
• Chlorophyll A • Lycopene
light energy,
• Chlorophyll B • Zeaxanthin Step 2: The energized electron is transferred to a primary
• Chlorophyll C • carotene electron acceptor (pheophytin).
• Chlorophyll D Step 3: To replace the electrons in p680, photolysis occurs.
• Bacteriochlorophyll Step 4: The electron in pheophytin passes along the electron
transport chain
• The photosynthetic apparatus is found in the thylakoid Step 5: p700 of photosystem I passes the electron to its primary
membrane acceptor
Step 6: Ferredoxin transfers the electron to NADP+ in the
presence of NADP+ reductase.

PHOTOSYSTEM
• Light Harvesting Complexes
o Consist of pigment molecules bound to proteins
o Funnel the energy of photons to the reaction
center
• Reaction Center
o Consists of:
§ Center chlorophyll
§ Primary electron acceptor
§ Core proteins

K. HERRERA | 12 - COTTAM 2
 MODULE 9: PHOTOSYNTHESIS

• Three (3) Phases

o Carbon Fixation
o Reduction
o Regeneration of CO2 Acceptor

Stage 1: Carbon Fixation

• Reaction: CO2 reacts with ribulose bisphosphate (RuBP)
• Catalyst: Ribulose bisphosphate carboxylase/oxygenase
(Rubisco)
• Product: 3-phosphpglycerate (3-PGA)

Stage 2: Reduction

(1)
• Reaction: 3-PGA is phosphorylated
CYCLIC ELECTRIC FLOW • Catalyst: 3-phosphoglycerate kinase
• Product: 1,3-bisphosphoglycerate (1,3-BPGA)
• Involves photosystem I, photosynthetic electron transport
chain, and ATP synthase (2)
• Produces ATP only • Reaction: 1,3-BPGA is reduced
• Cyclic electron flow happens simultaneously with the non- • Catalyst: NADP:glyceraldehyde-3- phosphatase
cyclic electron flow. • Product: Glyceraldehyde-3-phosphate (G3P)

• Glyceraldehyde-3-phosphate
o a) used for the regeneration of RuBP
o b) used to synthesize other organic molecules

Step 3: RUBP Regeneration

• Reaction:
o G3P undergoes a series of reactions including:
§ isomerization
§ condensation
§ hydrolysis
§ phosphorylation
o Product: Ribulose bisphosphate (RuBP)

RUBISCO (RIBULOSE BISPHOSPHATE

CARBOXYLASE/OXYGENASE)
• An important property of RUBISCO is that it has the ability
to catalyze both carboxylation or the addition of carbon
dioxide into a molecule and oxygenation which adds up
Products of Light Reaction:
oxygen, hence the name Ribulose Bisphosphate
• NADPH
Carboxylase or Oxygenase.
• ATP
• Photorespiration – oxygenation instead of carboxylation
• O2 decreases the efficiency of Photosynthesis (because
what it fixes in the c3 cycle or the calvin cycle is not carbon
SYNTHESIS dioxide but oxygen, therefore, there is a loss of carbons in
(B) CARBON REACTIONS the cycle.)
• Use ATP and NADPH to form sugar from CO2 • When does photorespiration happen?
• Occur in the stroma o Concentration of substrates (O2>CO2) (when
• Produce sugar (G3P) plants are exposed to an environment which has
greater amount of atmospheric oxygen than
THE STROMA carbon dioxide)
• Contains: o Temperature (the amount of atmospheric oxygen
o Chloroplast DNA tends to become more than the atmospheric
o Enzymes carbon dioxide, thus, it increases the chance that
o Metabolic products RUBISCO fixes oxygen instead of carbon dioxide)
• The biological importance of photorespiration is not yet
THE CALVIN-BENSON CYCLE known. However. There are some probable importance of
this where in photorespiration is believed to prevent
• Requirements: damage of photosynthetic apparatus of plants that are
o CO2 placed in light intensity and low carbon dioxide carbon
o ATP and NADPH concentration because stomata have to close to prevent
o Ribulose-1-5-bisphosphate (RuBP) water loss.
o Enzymes

K. HERRERA | 12 - COTTAM 3
 MODULE 9: PHOTOSYNTHESIS

CARBON REACTIONS: C4 CAM

• Alternative Mechanisms of Carbon Fixation
Bundle sheath and
Mesophyll
mesophyll
Spatial separation Temporal separation
4-carbon compound 4-carbon compound
PEP carboxylase (day) PEP carboxylase (night)
Sugarcanes, corns Cacti, pineapples

Light Reactions VS Carbon Reactions

Light Reactions Carbon Reaction

Carried out by the molecules
Take place in the stroma
HATCH SLACK PATHWAY (C4) in the thylakoid membrane
• Uses mesophyll and bundle sheath cells Use ATP and NADPH to
Convert light energy to ATP
• Incorporate CO2 into four-carbon compounds and NADPH
synthesize glyceraldehyde-
• Primary CO2 acceptor is phosphoenolpyruvate (PEP) 3-phosphate (G3P)
• Advantages: Utilize photosystems and Utilize enzymes and CO2
o Reduce stomatal aperture electron carriers acceptors
o Can operate at low co2 conc.
o Photosynthesize more efficiently at high Non-cyclic & cyclic electron
C3, C4, and CAM pathway
temperatures flow
o Suppresses photorespiration

Lecture Video / Sources:

Introduction to Photosynthesis:
https://www.youtube.com/watch?v=qlMlpfXnODw
Light Reactions:
https://www.youtube.com/watch?v=RLulqvyP_XY
Carbon Reactions:
https://www.youtube.com/watch?v=KbC1UFQobs8
Adaptations to Photorespiration:
https://www.youtube.com/watch?v=2tlNlGlGaUk

CRASSULACEAN ACID METABOLISM (CAM)

• Stomates are open at night and are closed during the day.
• Uses rubisco and PEP carboxylase
• Incorporate CO2 into organic acids.
• Advantages:
o Maximum water use efficiency
o Operates in extremely dry environments
o Suppresses photorespiration
•

K. HERRERA | 12 - COTTAM 4
GENERAL BiOLOGY 1 / MR. REYMARK PLACAMBO SEM

CELLULAR RESPiRATiON 01
[MODULE 10] CELLULAR RESPIRATION

CELLULAR RESPIRATION REUCTION REACTION

• The process by which an organism uses oxygen (O2) to • The gain of electrons to a substance
breakdown food molecules to get chemical energy for cell • Or the loss of oxygen
function.
• A catabolic, exergonic, oxygen (O2) requiring process
that uses energy extracted from macromolecules
(glucose) to produce energy (ATP) and water (H2O).

PATHWAY OF CELLULAR RESPIRATION

In what kind of organisms does cellular respiration take

place?

PLANTS AND ANIMALS

• Plants – Autotrophs: self-producers
• Animals – Heterotrophs: consumers

MITOCHONDRIA
• Organelle where cellular respiration takes place.

BREAKDOWN OF CELLULAR RESPIRATION

• Four main parts (reactions)
o Glycolysis (splitting of sugar)
§ Cytosol, just outside of mitochondria
o Grooming Phrase / Pyruvate Oxidation
§ Migration from cytosol matrix
o Krebs Cycle (Citric Acid Cycle)
§ Mitochondrial matrix
REDOX REACTION o Electron Transport Chain (ETC) and Oxidative
• Transfer of one or more electrons from one reactant to Phosphorylation
another. § Also called Chemiosmosis
• Two Types: § Inner mitochondrial membrane
o Oxidation
o Reduction SUBSTRATE LEVEL PHOSPHORYLATION
• We use the term
OXIDATION REACTION substrate level
• The loss of electrons from a substance phosphorylation
• Or the gain of oxygen because ATP
formation is
powered by the
addition/removal
of phosphate
groups
(phosphorylation)
to molecules of
glucose (the
substrate).

K. HERRERA | 12 - COTTAM 1
 MODULE 10: CELLULAR RESPIRATION

OXIDATIVE PHOSPHORYLATION three carbons each. In the process, no ATP molecule is

• We use the term spent but has produced four ATP molecules and two NADH
oxidative molecules. Hence, the name, energy harvesting or energy
phosphorylation to yielding phase.
describe how
molecules of FADH2
and NADH (produced
in the Citric Acid cycle)
are used to make ATP.
• We use the term
“oxidative” because
oxygen accepts an
electron while the gradient made by the movement of
electrons powers the creation ATP.

GLYCOLYSIS
• Occurs in the cytosol just outside of mitochondria.
• Two Phases (10 steps): TOTAL NET YIELD
o Energy investment phase
• 2 – Pyruvate (PYR)
§ Preparatory phase (5 steps)
• 2 – ATP (Substrate-level Phosphorylation)
o Energy yielding phase
o We only have two ATP molecules instead of four
§ Energy payoff phase (second 5 steps)
because we used or invested two ATP molecules
•
during the first five steps.
• 2 - NADH

Note: Glycolysis is anaerobic or it happens without the presence

of oxygen.

FERMENTATION
• Occurs in cytosol when “no oxygen” is present (called
anaerobic).
• Remember: Glycolysis is part of fermentation
• Two Types:
o Alcohol Fermentation
o Lactic Acid Fermentation

ALCOHOL FERMENTATION
• Plants and Fungi → beer and wine
• This type of fermentation happens in plant and fungi and in
ENERGY INVESTMENT PHASE industry, this fermentation is used to create beers and wines
• The glucose molecule which contains 6 carbons is cleaved and other food and beverages that we consume. It starts
into two molecules of glyceraldehyde 3 phosphate which first in glycolysis, wherein a glucose molecule is cleaved
contains 3 carbons each. In these first five steps, the into two molecules of pyruvic acid or pyruvates. In the
cleaving makes use of two molecules of ATP. Hence, this process, there is a net yield of two ATPs and two NADH
is called Energy Investment Phase because it makes use molecules. Now if there is still no oxygen, fermentation
of ATP molecules 9there is an investment of ATP happens.
molecules). • In alcohol fermentation, the two pyruvic acids are going to
be removed with carbon specifically in the form of carbon
dioxide. One carbon dioxide is removed in every pyruvic
acid. Since there is two, there is a release of two molecules
of carbon dioxide. Also, aside from the carboxylation, the
molecules are also going to be reduced by the electrons
coming from NADH. Since we have two molecules in the
process, we also need two molecules of NADH. These two
NADH once oxidized, they go back to the glycolysis ready
again to be reduced.
• In the end of alcohol fermentation, the final products are two
molecules of ethanol which contain two carbons each.

ENERGY YIELDING PHASE

• Energy Harvesting Phase
• The two molecules of G3P are just going to undergo a
series of chemical reactions making it now in the end, two
molecules of pyruvates or pyruvic acid which still contains

K. HERRERA | 12 - COTTAM 2
 MODULE 10: CELLULAR RESPIRATION

• The two pyruvates or the two pyruvic acids coming from the
cytosol produces through glycolysis will now enter the
mitochondrion. Upon entering, these molecules are going
to be oxidized by giving their electrons into two molecules
of NAD. Since there are two pyruvates, two NAD molecules
are reduced into NADH. Also, the pyruvic acids are going
to be decarboxylated releasing now two molecules of
carbon dioxide in which one comes from each pyruvate,
leaving two molecules of acetyl which contains two carbons
each. These two acetyl molecules immediately binds into a
coenzyme which is called as coenzyme A to enter now the
mitochondrion forming now a complex called as the acetyl
END PRODUCTS: ALCOHOL FERMENTATION CoA.
• 2 – ATP (substrate-level phosphorylation)
• 2 – CO2 END PRODUCTS: GROOMING PHASE
• 2 – Ethanols • 2 – NADH
• 2 – CO2
LACTIC ACID FERMENTATION • 2 Acetyl CoA (2C)
• Animals (pain in muscle after a workout)
• This type of fermentation happened to animals and this is KREBS CYCLE (CITRIC ACID CYCLE)
the reason why we get muscle sores after a workout or a • Location: mitochondrial matrix
heavy work (pamaol in Bisaya). After glycolysis, if there is • Acetyl CoA (2C) bonds to Oxaloacetic acid (4C – OAA)
no oxygen and if the organism is an animal, its cell will to make Citrate (6C).
undergo lactic acid fermentation. The two pyruvic acid or • It takes 2 turns of the Krebs cycle to oxidize 1 glucose
the two pyruvates are reduced by the electrons coming from molecule
the NADH. Since we have two pyruvic molecules, we also
need two NADH molecules. These two NADH molecules
are oxidized and once oxidized, they go back to glycolysis
ready to be reduced again into NADH so that it makes now
the process efficient.
• In the end, two lactic acids are formed and this lactic acid is
what clumps up in our muscle cells when we do workout.
Since this is acidic, it causes now the burning sensation that
we feel t=but eventually this pain is eliminated after a few
days because this process is going to be reversed by our
body.

END PRODUCTS: LACTIC ACID FERMENTATION

• 2 – ATP (substrate-level phosphorylation)
• 2 – Lactic Acids

PYRUVATE OXIDATION / GROOMING PHASE

• Occurs when Oxygen is present (aerobic).
• 2 Pyruvate (3C) molecules are transported through the
mitochondrial membrane to the matrix and is converted
to 2 Acetyl CoA (2C) molecules.
• The initial steps starts with the binding of the Acetyl CoA
with OAA forming now a six carbon compound which is
called as the citrate. Now this citrate is going to undergo a
series of chemical reactions, and in the process, there is a
release of two molecules of carbon dioxide, a production of
three molecules of NADH, a production or generation of one
molecule of ATP through substrate-level phosphorylation,

K. HERRERA | 12 - COTTAM 3
 MODULE 10: CELLULAR RESPIRATION

and one molecule of FADH2 from one Acetyl CoA. But since be used now to create ATP molecules through the enzyme
we have two Acetyl CoA from one glucose molecule, called the ATP synthase.
therefore it takes two turns. And in two turns, these are the • As the protons go back to the matrix, the kinetic energy is
products: harnessed by the ATP synthase to phosphorylate now ADP
o There is a release of four carbon dioxide molecules. Also, at the end part of the chain, the electrons
o A production of 6 NADH molecules are going to be used by the oxygen molecules to be
o A generation of two ATP molecules through reduced into water to make now the chain flowing or
substrate-level phosphorylation continuous. The produced water now leaves the cell and
o A production of two molecules of FADH2 eventually the body through sweats or urine. Hence, we
become sweaty when we work out because of the
increased supply of oxygen and its reduction into water.
Therefore, this means oxygen is very important because it
acts as the final electron acceptor in the Electron Transport
Chain.

ETC AND OXIDATIVE PHOSPHORYLATION

(CHMIOSMOSIS FOR FADH2)
• This presents the oxidation of FADH2. Now the oxidation of
NADH and FADH2 is just the same, except to the first
protein that accepts their electrons. The FADH2 immediately
donates its electrons to the second protein complex which
is this one. This means now it can move lesser number of
protons from the matrix to the inter membrane space.
• As the electrons move across or move through the Electron
Transport Chain, it has only moved approximately three
TOTAL NET YIELD (2 TURNS OF KREBS CYCLE)
hydrogen protons. But as you can see in the movement of
• 2 – ATP (substrate-level phosphorylation)
electrons coming from NADH molecules, it has moved six
• 6 – NADH molecules or six hydrogen protons. Therefore, there is a
• 2 – FADH2 difference on the number of ATPs that they generate.
• 4 – CO2

ELECTRON TRANSPORT CHAIN (ETC) AND

OXIDATIVE PHOSPHORYLATION (CHEMIOSMOSIS)
• Location: inner mitochondrial membrane
• Uses ETC (cytochrome proteins) and ATP Synthase
(enzyme) to make ATP.
• ETC pumps H+ (protons) across inner membrane (lowers
pH in inter-membrane space).

• The H+ then move via diffusion (Proton Motive Force)

through ATP Synthase to make ATP.
• All NADH and FADH2 are oxidized to make ATP during this
stage of cellular respiration.
• Each NADH is equivalent to 3 ATP
• Each FADH2 is equivalent to 2 ATP (enters the ETC at a
lower level than NADH).

EUKARYOTES (HAVE MEMBRANES)

• In the process, what are being used in the Electron • Total ATP Yield
Transport Chain are the NADH and the FADH2. The figure o 36 ATP Total
above present the oxidation of the NADH. In this figure, the
NADH molecules are oxidized, meaning they lose
electrons. Their electrons are given to the first protein
complex in the chain. The electrons now are going to be
passed from one protein to another protein until they reach
the last protein in the chain. As the electrons pass through
the protein complexes, it powers up now the movement of
hydrogen protons from the matrix to the inter membrane
space, forming now a gradient or an imbalance. Therefore,
there is a potential energy. This potential energy is going to

K. HERRERA | 12 - COTTAM 4
 MODULE 10: CELLULAR RESPIRATION

MAXIMUM ATP YIELD FOR CELLULAR In addition to glucose, what other various food molecules
RESPIRATION (EUKARYOTES) are used in Cellular Respiration?

CATABOLISM OF VARIOUS FOOD MOLECULES

• Other organic molecules used for fuel.
o Carbohydrates: polysaccharides
o Fats: glycerols and fatty acids
o Proteins: amino acids

Lecture Video / Source:

Introduction to Cellular Respiration:

https://www.youtube.com/watch?v=CqcmuvOOZAo
Glycolysis and Fermentation:
https://www.youtube.com/watch?v=57MlMf9bRQA
Pyruvate Oxidation and Krebs Cycle:
• In glycolysis, the glucose is broken down into two molecules https://www.youtube.com/watch?v=d_jMLbmOx3Q
of pyruvates and also in glycolysis, there is a production of ETC and Oxidative Phosphorylation:
two ATP molecules through substrate level https://www.youtube.com/watch?v=WvKyVh_e-Bw
phosphorylation. Aside from that, there is also a production
of two molecules of NADH. Now in pyruvate oxidation,
these two pyruvates are going to enter now the
mitochondrion, specifically the mitochondrial matrix. Now
the process these two pyruvates are converted into two
molecule od Acetyl CoA. And in the conversion, there is a
production of two molecules of NADH, and these two NADH
molecules are going to be processed in the Electron
Transport Chain. Therefore, this can now generate six ATP
molecules. Now these two Acetyl CoA is going to enter the
Krebs cycle. In this cycle there is a production of two
molecules of ATP through substrate-level phosphorylation.
And in the two cycles, it can produce six molecules of NADH
and two FADH2, which are later on again used in the
Electron Transport Chain. Again, these NADH molecules is
equivalent to 18 molecules of ATP and two FADH2
molecules is equivalent to four ATP molecules. Now, these
two NADH molecules coming from glycolysis are also going
to enter the mitochondrion. Upon entering the
mitochondrion, there is the expenditure of two ATP
molecules, one ATP is spent in one NADH molecule.
Therefore, instead of putting here six, there is only 4 ATP
molecules. It’s because it needs two ATP molecules in
order for these two NADH molecules to enter now the
mitochondrion for the Electron Transport Chain.

PROKARYOTES (LACK MEMBRANES)

• Total ATP Yield
o 38 ATP Total

K. HERRERA | 12 - COTTAM 5