Simplified Module 2

In
GENERAL BIOLOGY 1
QUARTER 1
CELL: THE BASIC UNIT OF LIFE

 Lesson 3 – Prokaryotic vs Eukaryotic Cells

 Lesson 4 – Cell Types
Cell Modifications

 Competencies:
1. Distinguish prokaryotic and eukaryotic cells according to their distinguishing
features STEM_BIO11/12-Ia-c-3
2. Classify different cell types (plant/animal tissues) and specify the function(s)
of each STEM_BIO11/12-Ia-c-4
3. Describe some cell modifications that lead to adaptation to carry out
specialized functions (e.g., microvilli, root hair) STEM_BIO11/12-Ia-c-5

Lesson 3 – Prokaryotic vs Eukaryotic Cells

What’s In

In lesson 2, you have learned about the cell structure and function of major and
subcellular organelles.
In this next topic, you will learn on prokaryotic and eukaryotic cells according to
their distinguishing features.

What I Need to Know

Prokaryotes vs Eukaryotes

Most living things you know such as animals and plants are
multicellular organisms. Some living things are made up of only single cell.
Single-celled or unicellular organisms include the bacteria, some protists, and
some fungi. Even though composed of single cells, these organisms carry out
all the functions necessary for life. In different organisms, cells also vary in
sizes, shapes, parts, and functions. But they all have one thing in common:
they make up all living things and they are living.
What’s New

Prokaryote Eukaryote

Direction: In the following matrix, put a check in the box to show the
organelle is present in prokaryotic or eukaryotic cells, or both, and state in
once sentence what function of the organelle is.

Organelle Prokaryote Eukaryote Function

Cell membrane
Cell wall
Nucleus
Mitochondria
chloroplast
Endoplasmic
reticulum
(smooth)
Golgi apparatus
Lysosomes
Ribosomes
Endoplasmic
reticulum (rough)
Vacuole

What Is It

There are two kinds of organisms according to their cell structure,

the prokaryotes and eukaryotes. The difference between prokaryotic and
eukaryotic organisms is said to be the most important distinction among the
groups of living things. Prokaryotes are single-celled organisms that lack a
membrane-bound nucleus, mitochondria, and all other organelles. Its name
comes from the Greek words pro, which means ―before‖, and karyon, which
means ―nut or kernel‖. Eukaryotes are organisms with cells that contain

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membrane-bound nucleus and other membrane-bound organelles. The
nucleus of a eukaryotic cell contains the genetic material (DNA), enclosed by
a nuclear envelope. Other membrane-bound organelles are mitochondria,
Golgi apparatus, and chloroplast found in photosynthetic organisms such as
algae and plants. There are also unicellular eukaryotes known as protozoa.
All other eukaryotes are multicellular organisms such as plants, animals, and
fungi.

What’s More

For the chart below, place a check in the box if the cell has that component.

Organelle Plant Animal Bacteria

Vacuole
Chloroplast
Ribosome
Mitochondria
DNA
Endoplasmic
Reticulum
Cell Wall
Golgi Appratus

What I Have Learned

Directions: On the lines below, write about what you‘ve learned by doing the
activities. Be as specific as possible and use COMPLETE SENTENCES.

1. Let me tell you some of the important things I‘ve learned about
prokaryotic and eukaryotic cells. First, I‘ll start with the difference
between prokaryotic and eukaryotic cells

_________________________________________________________________
_________________________________________________________________
_________________________________________________________________.

2. Next, I‘ll tell you examples of prokaryotic and eukaryotic cells

_________________________________________________________________
_________________________________________________________________
_________________________________________________________________.

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 3. Lastly, I now really know about and understand that prokaryotic and
eukaryotic cells

________________________________________________________________
________________________________________________________________
________________________________________________________________.

What I Can Do

Directions: Draw a prokaryotic (bacteria) and eukaryotic cell on a

separate sheet of paper. Label the prominent structures and if possible
note the name of the species.

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Lesson 4 – Cell Types and Cell Modifications

What’s In

In lesson 3, you have learned about the difference between prokaryotic and
eukaryotic cells according to their distinguishing features.
In this next topic, you will learn on the classification of different cell types and
cell modifications that lead to adaptation to carry out specialized functions.

What I Need to Know

There are certain characteristics that all living things exhibit, the
characteristics of life. Living things are made up of cells. They metabolize,
grow and develop, respond to stimulus, adapt to their environment and
reproduce. Life on Earth exhibits organization. The atom is smallest unit of
matter, followed by molecules, which are combinations of atoms. When these
molecules are grouped together, they ultimately form a cell. The cell is the
basic unit of life. In multicellular, organisms like plants and animals, cells are
grouped as tissues to perform a specific function. Different tissues can be
grouped further and form organs. The organs form organ systems that makes
the function of the body more complex and efficient. Organs system will then
form the whole organisms. All living things exhibit organization, whether they
are unicellular or multicellular organisms.

What’s New

Direction: Arrange the words according to the levels of biological

organization.

organ system organism tissue cell

What Is It

There are hundreds of types of cells, but the four main types are
epithelial cells, connective tissue cells, muscle cells and nerve cells.

Epithelial Tissue—This type of tissue is commonly seen outside the body as

coverings or as linings of organs and cavities. Epithelial tissues are
characterized by closely-joined cells with tight junctions (i.e., a type of cell
modification). Being tightly packed, tight junctions serve as barriers for
pathogens, mechanical injuries, and fluid loss.

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Cells that make up epithelial tissues can have distinct arrangements:

• cuboidal—for secretion
• simple columnar—brick-shaped cells; for secretion and active absorption
• simple squamous—plate-like cells; for exchange of material through
diffusion
• stratified squamous—multilayered and regenerates quickly; for
protection
• pseudo-stratified columnar—single layer of cells; may just look stacked
because of varying height; for lining of respiratory tract; usually lined with
cilia (i.e., a type of cell modification that sweeps the mucus).

Figure 1: Epithelial Tissue (Source: Reece JB, U. L. (2010). Campbell Biology

10th.
San Francisco (CA).)

Connective Tissue—These tissues are composed of the following:

BLOOD —made up of plasma (i.e., liquid extracellular matrix); contains

water, salts, and dissolved proteins; erythrocytes that carry oxygen (RBC),
leukocytes for defense (WBC), and platelets for blood clotting.

CONNECTIVE TISSUE PROPER (CTP)—made up of loose connective tissue

that is found in the skin and fibrous connective tissue that is made up of

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collagenous fibers found in tendons and ligaments. Adipose tissues are also
examples of loose connective tissues that store fats which functions to
insulate the body and store energy.
CARTILAGE —characterized by collagenous fibers embedded in chondroitin
sulfate. Chondrocytes are the cells that secrete collagen and chondroitin sulfate.
Cartilage functions as cushion between bones.

BONE —mineralized connective tissue made by bone-forming cells called

osteoblasts which deposit collagen. The matrix of collagen is combined with
calcium, magnesium, and phosphate ions to make the bone hard. Blood
vessels and nerves are found at a central canal surrounded by concentric
circles of osteons.

Figure 2: Connective Tissue (Source: Reece JB, U. L. (2010). Campbell Biology

10th. San Francisco (CA):.)

Muscle Tissue—These tissues are composed of long cells called muscle

fibers that allow the body to move voluntary or involuntary. Movement of
muscles is a response to signals coming from nerve cells. In vertebrates,
these muscles can be categorized into the following:

• skeletal—striated; voluntary movements

• cardiac—striated with intercalated disk for synchronized heart contraction;
involuntary
• smooth—not striated; involuntary

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Figure 3: Muscle Tissue (Source: Reece JB, U. L. (2010). Campbell Biology
10th. San Francisco (CA):.)

Nervous Tissue—These tissues are composed of nerve cells called neurons

and glial cells that function as support cells. These neurons sense stimuli and
transmit electrical signals throughout the animal body. Neurons connect to
other neurons to send signals. The dendrite is the part of the neuron that
receives impulses from other neurons while the axon is the part where the
impulse is transmitted to other neurons.

Figure 4: Neurons and Glial Cells (Source: Reece JB, U. L. (2010). Campbell
Biology 10th. San Francisco (CA):.)

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What’s More

Direction: Match each general tissue category to the appropriate feature. Write
the letter of your choice before each number.

A. Connective tissue
B. Epithelium
C. Muscular tissue
D. Nervous tissue

_____1. A type of tissue that would make up the majority of the brain and
spinal cord?
_____2. Found in the epidermis and form the lining of internal organs such as the
intestines
_____3. Form the ligaments, tendons, fat and bone
_____4. A type of tissue that makes up majority of the
heart

What I Have Learned

Direction: Identify which type of connective tissue (A-C), epithelial tissue (D-
F), and muscle tissue (G-I) is being described.

A. _______________transport oxygen, carbon dioxide, nutrients and waste

through the body by travelling through the vessels called arteries and veins.
B. _______________is a type of dense connective tissue that connects muscles
to bones and connects bone to bone.
C. _______________is a type of connective tissue with one of the hardest
extracellular matrixes that forms a protective structure used for muscle
attachment.
D. _______________found in respiratory tract (trachea), usually lined with cilia.
E. _______________found in air sacs/alveoli of the lungs, capillaries.
F. _______________found in digestive tract for secretion and active absorption
G. _______________muscles of the heart; involuntary movements.
H. _______________involuntary contractions of digestive tract like esophagus,
stomach and intestines.
I. ________________striated; voluntary movements like biceps and abdominal
muscles.

What I Can Do

Direction: Give at least 4 examples of the four major tissue types. Be as

specific as possible in giving examples.

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 KEY ANSWERS

LESSON 3 PROKARYOTIC VS EUKARYOTIC CELLS

What’s New

Organelle Prokaryote Eukaryote Function

Cell membrane √ √
Cell wall √ complex √ plants
Nucleus
Mitochondria
chloroplast
Endoplasmic
reticulum (smooth)
Golgi apparatus
Lysosomes
Ribosomes √smaller √ larger
Endoplasmic √
reticulum (rough)
Vacuole √ √

What’s More

Organelle Plant Animal Bacteria

Vacuole √ √ √
Chloroplast √
Ribosome √ √ √
Mitochondria √ √
DNA √ √ √
Endoplasmic √ √
Reticulum
Cell Wall √ √
Golgi Apparatus √ √

LESSON 4 CELL TYPES AND CELL MODIFICATION

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What’s new

cell tissue organ system organism

What’s More

1. D
2. B
3. A
4. C

What I Have Learned

A. BLOOD
B. CARTILAGE
C. BONE
D. PSEUDO-STRATIFIED COLUMNAR
E. SIMPLE SQUAMOS
F. SIMPLE COLUMNAR
G. CARDIAC
H. SMOOTH
I. SKELETAL

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