GENERAL BIOLOGY 1
STEM Specialized Subject
Class No.:
Name:
Grade and Section:
Date:
Module 1 – 1st Quarter – SY20212022
Teacher:
I.
Title: Introduction to Cell Biology: Cell Theory, Cell Organelles and Cell Types
II.
Objectives:
After accomplishing this module, you must be able to:
1. explain the postulates of cell theory;
2. describe the structure and function of major and subcellular organelles;
3. distinguish prokaryotic from eukaryotic cells according to their distinctive features;
4. value the importance of the origin of life; and
5. create an infographic about the different cell organelles in a living cell.
III.
Material/s:
1. Lecture Notes about the Introduction to Cell Biology
2. For Reference(s):
 YouTube video for review - https://www.youtube.com/watch?v=ivGgYgAB0A
https://www.youtube.com/watch?v=OssfJpkEjLk
https://www.youtube.com/watch?v=uczHXIlChws
https://www.youtube.com/watch?v=JAmTM9qnHBU
https://www.youtube.com/watch?v=9D9BhbTwZ5o
https://ed.ted.com/lessons/the-wacky-history-of-cell-theory)
IV.
Time Frame: Week 1 – Days 1- 3
V.
Concept:
Cell biology is one of the many branches of Biological Science which focuses on the study
of structures and functions of cells.
LESSON 1: CELL ORGANELLES
Cells are the basic building blocks of all living things. The human body is composed of
trillions of cells. They provide structure for the body, take in nutrients from food, convert
those nutrients into energy, and carry out specialized functions. Cells also contain the body’s
hereditary material and can make copies of them. Cells have many parts, each with a
different function. Some of these parts, called organelles, are specialized structures that
perform certain tasks within the cell.(see fig. 1)
General Biology 1 – Module 1
Page 1 of 7
LESSON 2: CELL THEORY
The CELL THEORY, or cell doctrine, states that all organisms are composed of similar units of
organization, called cells. The concept was formally articulated in 1839 and has remained as
the foundation of modern biology. The idea predates other great paradigms of biology
including Darwin's theory of evolution (1859), Mendel's laws of inheritance (1865), and the
establishment of comparative biochemistry (1940). The invention of the microscope allowed the
discovery of the cell by Robert Hooke in 1665. This discovery then led to the formulation of the
cell theory by Matthias Jakob Schleiden, Theodor Schwann and Rudolf Virchow. It states the
following postulates:
1. All living organisms are composed of one or more cells.
2. The cell is the basic unit of life in all living things
3. All cells come from preexisting cells.
LESSON 3: CELL TYPES: Prokaryotic vs Eukaryotic Cell
Cells fall into one of two broad categories: prokaryotic and eukaryotic. The single-celled
organisms of the domains Bacteria and Archaea are classified as prokaryotes (pro =
before; karyon– = nucleus). Animal cells, plant cells, fungi, and protists are eukaryotes (eu = true).
Components of Prokaryotic Cells
All cells share four common components: (1) a plasma membrane, an outer covering that
separates the cell’s interior from its surrounding environment; (2) cytoplasm, consisting of a jellylike region within the cell in which other cellular components are found; (3) DNA, the genetic
material of the cell; and (4) ribosomes, particles that synthesize proteins. However, prokaryotes
differ from eukaryotic cells in several ways.
A prokaryotic cell is a simple, single-celled (unicellular) organism that lacks a nucleus, or any
other membrane-bound organelle. We will shortly come to see that this is significantly different in
eukaryotes. Prokaryotic DNA is found in the central part of the cell: a darkened region called the
nucleoid (Figure 1).
Unlike Archaea and eukaryotes, bacteria have a cell wall made of peptidoglycan, comprised of
sugars and amino acids, and many have a polysaccharide capsule (Figure 1). The cell wall acts
as an extra layer of protection, helps the cell maintain its shape, and prevents dehydration. The
capsule enables the cell to attach to surfaces in its environment. Some prokaryotes have flagella,
pili, or fimbriae. Flagella are used for locomotion, while most pili are used to exchange genetic
material during a type of reproduction called conjugation.
Eukaryotic Cells
In nature, the relationship between form and function is apparent at all levels, including the level
of the cell, and this will become clear as we explore eukaryotic cells. The principle “form follows
function” is found in many contexts. It means that, in general, one can deduce the function of a
structure by looking at its form, because the two are matched. For example, birds and fish have
streamlined bodies that allow them to move quickly through the medium in which they live, be it
air or water.
A eukaryotic cell is a cell that has a membrane-bound nucleus and other membrane-bound
compartments or sacs, called organelles, which have specialized functions. The word eukaryotic
means “true kernel” or “true nucleus,” alluding to the presence of the membrane-bound nucleus
in these cells. The word “organelle” means “little organ,” and, as we learned earlier, organelles
have specialized cellular functions, just as the organs of your body have specialized functions.
General Biology 1 – Module 1
Page 2 of 7
VI.
Activity: Let’s try these!
DAY 1
A. Directions. Match column A with column B. Write your answer on the blank provided
before each number.
COLUMN A
COLUMN B
D
1. Golgi bodies
A. Synthesis of protein
B
2. Lysosomes
B. Digestion of larger molecules
E
3. Mitochondrion
C. Storage and maintaining of homeostasis
A
4. Ribosome
D. Sorting, packaging and transport of proteins
C
5. Vacuole
E. Energy production of the cell, ATP production
F. Synthesis and processing of proteins, lipids
expression
DAY 2
B. Directions. Read the questions below and encircle theletter of the correct answer.
A
1. The belief that life comes from preexisting life is called
.
A. Abiogenesis
B. Biogenesis
C. Creationism
D. Panspermia
B
2. The theory proposed by Schleiden, Schwann and Virchow is
called
.
A. Big Bang Theory
C. Theory of Relativity
B. Cell Theory
D. Theory of Spontaneous Generation
C
3. Which of the following is FALSE about the cell theory?
A. The cells theory asserts that cells will arise only from existing cells.
B. The cell theory supports the belief that life comes from non-living things.
C. The cell theory states that living things are either unicellular or multicellular.
D. The cell theory declares the cell as the fundamental unit of structure in living
things.
A
4. All life comes from existing life. Which of the following BEST describes this
statement?
A. biological levels of organization
C. multicellular plants and animals
B. human pregnancy
D. unicellular amoeba
B
5. Which of the following sequences represents the levels of biological organization
from the least tothe most complex level?
A. atom, organelle, molecule
C. organism, community, population
B. cell, tissue, organ
D. organ, organism, organ system
C. Directions. Read and understand the paragraph below. Then, answer the given questions.
An efficiency apartment is a one-room apartment. This one room is where you sleep,
eat, shower, and entertain your guests. It all happens in one room. It is a simple way of
living in a small space. Unlike mansion, that is large, has a complex living space with
many separate rooms for cooking, eating, sleeping, bathing, reading, watching TV,
entertaining guests, exercising, and storage. Either way, you can live in simple efficiency
or complexity. In this activity, we will be looking at cells that are as simple as a one-room
efficiency apartment or as complex as a mansion. Refer to the two (2) apartment models
to answer all the queries stated below.
General Biology 1 – Module 1
Page 3 of 7
APARTMENT MODELS
MODEL 1
3 Types of Bacterial Cells
MODEL 2
Animal and Plant Cells
QUESTIONS:
1. What is represented by the small dots found in each bacterial cell?
The small dots found in existence in every one of the bacterial cells are described as
ribosomes.
2-3. How is the DNA described in Model 1 and what does this mean?
4-5. What can you infer about the absence of tail-like structure in the two other types of
bacterial cells? flagella, hairlike construction that acts as an organelle of velocity in the
cells of many living beings. Flagella, normal for the protozoan gathering Mastigophore,
likewise happens on the gametes of green growth, parasites, greeneries, ooze molds,
and creatures.
6-8. List the differences between animal and plant cells.
- Plant cells have a cell wall, but animal's cells do not.
- Plant cells usually have one or more large vacuole(s), while animal cells have
smaller vacuoles, if any are present.
9-11. Compare the outer boundaries of plant and animal cell wall.
Animal cells do not have a cell wall. Instead of a cell wall, the plasma membrane
(usually called cell membrane when discussing animal cells) is the outer boundary of
animal cells. Cell wall Protects cell externally and the cell membrane Protects cell
internally
12-15. Decide which of the two apartments will you rent? Explain your answer.
General Biology 1 – Module 1
Page 4 of 7
VII.
Evaluation: Let’s check your understanding! (Quiz No.1 - 30 points)
A. Multiple Choice. Choose the best answer for each given item.
D
B
D
A
A
1. In plant cells, a large, fluid-filled space inside the cell that helps the cell
maintain its shape and may also be used to store nutrients and waste products.
In animal cells, small fluid spaces inside the cell that are used to store nutrients
and waste products. Name this organelle.
A. Cell wall
C. Ribosome
B. Chloroplast
D. Vacuoles
2. When a cell is deprived of oxygen, its lysosomes tend to burst and release
their contents into the cell. As a result of this, that cell is expected to
.
A. undergo cell division
C. recycled damage organelles
B. undergo self-digestion and die
D. produce replacement for lysosomes
3. Which of the following organelles ensure that after cell division each
daughter cell has the correct number of chromosomes?
A. Nucleus
C. Cytoskeleton
B. Endoplasmic reticulum
D. Centriole
4. Which of the following is TRUE about the nucleus?
A. The nucleus is known as the control C. All cells have a nucleus.
center of the cell.
D. All of the above.
B. The nucleus contains the entire
cell’s DNA.
5. What cell structure can determine the molecules that can enter and leave the
cell?
B. Lysosome
C. Chloroplast
D. Cell wall
A. Plasma
membrane
B. Write A if both statements are true; B if the first statement is true and the second is false;
C is the first statement is false and the second is true; and D if both statements are false.
D
A
C
D
A
6. Robert Hooke called the structures he observed under the microscope animalcules.
Anton van Leeuwenhoek coined the term cell after viewing cork tissue through lens.
7. Golgi bodies are stacks of flattened membranous sacs involved in receiving,
sorting, packing and transporting products in the cell.
Vacuoles are large single membrane-bounded vesicle for digestion, storage, waste
disposal, water balance, cell growth, and protection.
8. Vesicles are involved in breaking down of ingested substances, cell macromolecules,
and damaged organelles for recycling.
Lysosomes move materials between organelles in the endomembrane system.
9. The smooth endoplasmic reticulum is also involved in protein synthesis.
The plasma membrane is often referred to as the fluid-mosaic model.
10. Ribosomes are the organelles involved in protein synthesis.
Nucleus has a perforated double-membrane structure.
C. Read and study the given paragraph below, then answer the following questions concisely.
Plasma Membrane
The plasma membrane forms a barrier between the cytoplasm inside the cell and the
environment outside the cell. It protects and supports the cell and also controls everything
that enters and leaves the cell. It allows only certain substances to pass through, while
keeping others in or out. The ability to allow only certain molecules in or out of the cell is
referred to as selective permeability or semipermeability. To understand how the plasma
membrane controls what crosses into or out of the cell, you need to know its composition.
Phospholipid Bilayer
The plasma membrane is composed mainly of phospholipids, which consist of fatty acids
and alcohol. The phospholipids in the plasma membrane are arranged in two layers, called
a phospholipid bilayer. As shown in the figure below, each phospholipid molecule has a
head and two tails. The head “loves” water (hydrophilic) and the tails “hate” water
General Biology 1 – Module 1
Page 5 of 7
(hydrophobic). The water-hating tails are on the interior of the membrane, whereas the
water-loving heads point outwards, toward either the cytoplasm or the fluid that surrounds
the cell. Molecules that are hydrophobic can easily pass through the plasma membrane, if
they are small enough, because they are water-hating like the interior of the membrane.
Molecules that are hydrophilic, on the other hand, cannot pass through the plasma
membrane — at least not without help — because they are water-loving like the exterior of
the membrane.
Other Molecules in the Plasma Membrane
The plasma membrane also contains other molecules, primarily other lipids and proteins.
The green molecules in the figure above, for example, are the lipid cholesterol. Molecules
of cholesterol help the plasma membrane keep its shape. Many of the proteins in the plasma
membrane assist other substances in crossing the membrane.
Extensions of the Plasma Membrane
The plasma membrane may have extensions, such as whip-like flagella or brush-like cilia.
In single-celled organisms, the membrane extensions may help the organisms move. In
multicellular organisms, the extensions have other functions. For example, the cilia on
human lung cells sweep foreign particles and mucus toward the mouth and nose.
QUESTIONS:
11. What is a plasma membrane?
Plasma membranes are subcellular structures, approximately 10nm thick, that form a protective
boundary around the cell as well as the cell’s organelles. They serve to both impede foreign
material from entering the cell and prevent the cellular contents from leaking out. With the
structural makeup of the lipid bilayer conferring membranes unique physical and chemical
properties, these structures also contribute to diverse and critical cellular functions.
12- 13. What is the meaning of semi permeability in cell?
Semipermeable membrane is a type of biological or synthetic, polymeric membrane that will
allow certain molecules or ions to pass through it by osmosis.
14- 16. Discuss why the plasma membrane must be a bilayer.
The lipid bilayer is the barrier that keeps ions, proteins, and other molecules where they are
needed and prevents them from diffusing into areas where they should not be.
17- 18. What are some of the “other” molecules in the plasma membrane? Describe their
function.
lipids (phospholipids and cholesterol), A phospholipid is a lipid made of glycerol, two fatty acid
tails, and a phosphate-linked head group. Biological membranes usually involve two layers of
phospholipids with their tails pointing inward, an arrangement called a phospholipid bilayer.
Cholesterol, another lipid composed of four fused carbon rings, is found alongside phospholipids
in the core of the membrane.
General Biology 1 – Module 1
Page 6 of 7
19- 20. What are cilia and flagella?
Cilia and Flagella are motile cellular appendages found in most microorganisms and animals,
but not in higher plants. In multicellular organisms, cilia help move cells or groups of cells, or
help transport liquids or substances through them.
General Biology 1 – Module 1
Page 7 of 7