SHS STEM - BIOLOGY 1
Quarter 1 – Module 13
Transport Mechanisms
(Endocytosis and Exocytosis)
i
General Biology 1 – Grade 11
Quarter 1 – Module 13: TRANSPORT MECHANISMS (ENDOCYTOSIS AND
EXOCYTOSIS)
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Regional Director: Gilbert T. Sadsad
Assistant Regional Director: Jessie L. Amin
DEVELOPMENT TEAM OF THE MODULE
WRITER:
Christine Lee B. Bayna
REVIEWERS/EDITORS:
Rowena D. Manaog
Freddierick C. Apuli
Ma. Lota C. Monte
Jade Alberto
LAYOUT ARTISTS:
Jay Mark Base
Jonathan Roda
Jessica De Ocampo
“Differentiate exocytosis and endocytosis.”
STEM_BIO11/12-Ig-h-14
TRANSPORT MECHANISMS (EXOCYTOSIS AND
ENDOCYTOSIS)
The new normal requires new routines, new ways of working, and as well as new
ways of teaching and learning. As we are currently facing this pandemic, education has
encountered another obstacle towards effective delivery. This, however, should not
hinder education to continue. The Department of Education looked into ways on how
education could still push through despite this health crisis.
This module is designed to supplement the available learning materials in the
Senior High School. The integration of this module with the alternative learning delivery
modalities will help to ensure that basic education will be accessible amidst the present
crisis. It is based on the Most Essential Learning Competencies (MELCs) as stipulated
by DepEd.
Teacher
The design of the module attempts to be adaptive to different learning modalities.
Orient the students, their parents, or those who will guide the learner on how to properly
utilize the module. Inform them of the different activities that they must accomplish and
the important dates to make sure of compliance.
Learner
This module was prepared for you. Make sure to answer and perform tasks
honestly. Take good care of this module and answer on a separate sheet of paper. Do
not forget to finish the tasks assigned to you by your teacher, as well as the period of
submission.
OBJECTIVES:
At the end of this module, you should be able to:
1. define endocytosis and exocytosis
2. differentiate endocytosis (phagocytosis and pinocytosis) and exocytosis
3. explain how materials enter and leave the cell through endocytosis and
exocytosis
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Endocytosis- the process by which large substances or bulk amounts of smaller
substances enter the cell without crossing the membrane
Exocytosis- the process by which large substances or bulk amounts of small
substances exit the cell without crossing the membrane
Phagocytosis – the process by which solid substances are ingested
Pinocytosis – the process by which liquids / dissolved substances are ingested
Plasma membrane- the membrane found in all cells that separates the interior of the
cell from the outside environment
Vesicles- are compartments formed by a lipid bilayer separating its contents from the
cytoplasm or a fluid-based extracellular environment
Instruction: Read each item carefully. Select the letter of the correct
answer and write it on a separate sheet of paper.
1. What cell organelle helps to transport large molecules into or out of the cell?
a. Nucleus
b. Ribosome
c. Mitochondria
d. Vacuole
2. Which is NOT true about endocytosis?
a. It requires energy to occur.
b. It occurs without the help of any cell organelle.
c. It takes in nutrients for cellular growth, function, and repair.
d. Phagocytosis and Pinocytosis are its types
3. Which is true about exocytosis?
a. It is a form of passive transport.
b. It occurs without the help of any cell organelle.
c. It removes toxins or waste products from the cell’s interior
d. Phagocytosis and Pinocytosis are its types
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4. Which is an example of endocytosis?
a. White blood cells engulfing a virus and eliminating it.
b. Releasing a neurotransmitter for cellular communication.
c. Both a and b
d. None of these
5. How are large substances transported through exocytosis?
a. When a portion of the cell membrane folds in on itself, encircling extracellular
fluid and various molecules or microorganisms.
b. When a vesicle fuses with the plasma membrane, allowing its contents to be
released outside the cell.
c. Both a and b
d. None of these
Instruction: Answer the following questions. Write your
answer on the space provided.
You are preparing your things for a group study.
While preparing, you noticed that your bag is
already full of stuffs and you still have some
things you want to bring. You only want to bring
one bag to avoid hassle, what are you going to
do?
https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.shutterstock.com%2Fimagevector%2Fseamless-women-bag-stuff-pattern-can442189447&psig=AOvVaw0rr8zsUlE3MQgjBCk9ZsMT&ust=1597117858175000&source=images&cd=vf
e&ved=0CAIQjRxqFwoTCNC7yJHej-sCFQAAAAAdAAAAABAV
Relate the situation above on how cells
transport materials into and out of the cell.
3
Instruction: Explain how materials are transported into and out of the
cell. Write your answer on the box provided.
https://www.google.com/url?sa=i&url=https%3A%2F%2Fbiologydictionary.net%2Factivetransport%2F&psig=AOvVaw2oaQfz49NHn44bcI1oyrTd&ust=1597119854216000&source=images&cd=
vfe&ved=0CAIQjRxqFwoTCOC9sMTlj-sCFQAAAAAdAAAAABAJ
https://www.google.com/url?sa=i&url=https%3A%2F%2Fbiologydictionary.net%2Factivetransport%2F&psig=AOvVaw2oaQfz49NHn44bcI1oyrTd&ust=1597119854216000&source=images&cd=
vfe&ved=0CAIQjRxqFwoTCOC9sMTlj-sCFQAAAAAdAAAAABAJ
4
Water and small solutes enter and leave the cell by diffusing
through the lipid bilayer of the plasma membrane or by being
pumped or moved across the membrane by transport proteins.
However,
large
molecules—such
as
proteins
and
polysaccharides, as well as larger particles—generally cross the membrane in bulk,
packaged in vesicles. Vesicles and cell membranes are both comprised of a lipid bilayer,
which is why they are capable of fusing with the cell membrane. This fusion between
vesicles and the plasma membrane facilitates bulk transport both into and out of the cell.
Like active transport, these processes require energy.
Endocytosis is the process by which cells take in substances from
outside of the cell by engulfing them in a vesicle. It occurs when a
portion of the cell membrane folds in on itself, encircling extracellular
fluid and various molecules or microorganisms. The resulting vesicle breaks off and is
transported within the cell. Endocytosis serves many purposes, including:
Endocytosis
➢ taking in nutrients for cellular growth, function, and repair.
➢ capturing pathogens or other unknown substances that may endanger the
organism.
➢ disposing of old or damaged cells
Types of Endocytosis
Reece, et.al., Campbell Biology, 138.
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Exocytosis is the process by which cells move materials from within
the cell into the extracellular fluid. It occurs when a vesicle fuses
with the plasma membrane, allowing its contents to be released outside the cell.
Exocytosis serves the following purposes:
Endocytosis
➢ removing toxins or waste products from the cell’s interior
➢ facilitating cellular communication
➢ facilitating cellular membrane growth, repair, signaling and migration
Types of Exocytosis
https://pediaa.com/difference-between-endocytosis-and-exocytosis/
In
constitutive
exocytosis,
extracellular signals are not required.
The majority of molecules traveling to
the plasma membrane do so using
this pathway.
In regulated exocytosis, the expulsion
of the materials is controlled, or
regulated, by extracellular signals that
cause membrane depolarization.
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Practice Task 1
Instruction: Write TRUE if the statement is correct, if
FALSE change the underlined word/s to make the
statement correct.
__________1. Endocytosis and exocytosis are types of passive transport.
__________2. In order for the cell to maintain homeostasis, waste materials are
removed from these cells via endocytosis.
__________3. In regulated exocytosis, the release of materials is controlled by
extracellular signals.
__________4. White blood cells engulfing a virus and eliminating it is an example of
exocytosis.
__________5. Endocytosis is the process of taking in a particle or substance from
outside of the cell using a vesicle.
__________6. Phagocytosis and Pinocytosis are types of endocytosis.
__________7. Vesicles are little sacs that separate its contents from the cytoplasm.
__________8. Exocytosis helps in facilitating cellular communication.
__________9. Pinocytosis is the process by which cells internalize large particles like
damaged cells and bacteria.
__________10. Disposing of old or damaged cells is done through Exocytosis.
Practice Task 2
Instruction: Compare endocytosis and exocytosis by
filling out the table below.
Endocytosis
Definition
Function
Types
Examples
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Exocytosis
Practice Task3
Instruction: Answer the following questions. Write your answer on the space
provided.
1. Explain how a phagocyte destroys bacteria.
2. Explain exocytosis in neurotransmission.
3. Do you think exocytosis and endocytosis can occur within the same cell?
4. Explain the importance of endocytosis and exocytosis.
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REFLECT!
ADDITIONAL QUERIES?
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Post-Test
Instruction: Read each item carefully. Choose the letter
of the BEST answer.
1. How are dissolved ions transported inside the cell?
a. Phagocytosis
c. Regulated
b. Pinocytosis
d. Constitutive
2. Which is NOT a function of exocytosis?
a. Removing toxins
b. Cellular membrane growth
c. Signaling and migration
d. Capturing pathogens
3. Which is a function of endocytosis?
a. Removing toxins
b. Facilitating cellular communication
c. Signaling and migration
d. Disposing damaged cells
4. Which of the following shows the correct steps in endocytosis?
I- The phagocytic vesicle fuses with lysosomes, which recycle or destroy the
vesicle’s contents.
II- A particle or substance binds to receptors on the cell’s surface, stimulating the
release of pseudopodia
III- Pseudopodia surround the object until their membranes fuse, forming a
phagocytic vesicle.
IV-The phagocytic vesicle pinches off from the cell membrane, entering the cell.
a. I, II, III, IV
c. III, IV, I, II
b. II, III, IV, I
d. IV, III, II, I
5. Which of the following shows the correct steps in exocytosis?
I-The vesicle fuses to the plasma membrane, during which the two bilayers
merge.
II- A vesicle is formed, typically within the endoplasmic reticulum and the Golgi
apparatus or early endosomes.
III-The vesicle’s contents are released into the extracellular space.
IV- The vesicle travels to the cell membrane.
a. I, II, III, IV
b. II, IV, I, III
c. III, IV, II, I
d. IV, III, I, II
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6. What is the difference between constitutive and regulated exocytosis?
a. Constitutive uses energy, regulated does not
b. Regulated uses energy, constitutive does not
c. Constitutive requires extracellular signals, regulated does not
d. Regulated requires extracellular signals, constitutive does not
7. Which of the following are types of endocytosis?
I-Phagocytosis
II-Pinocytosis
III-Constitutive
IV-Regulated
a.
b.
c.
d.
I and II
III and IV
I, II, and III
I, II, III, and IV
8. Which is NOT an active transport?
a. Phagocytosis
b. Pinocytosis
c. Endocytosis
d. None of these
9. What process takes in substances into the cell?
a. Phagocytosis
b. Pinocytosis
c. Endocytosis
d. All of the above
10. Which process does NOT transport substances outside the cell?
a. Regulated
b. Constitutive
c. Pinocytosis
a. Exocytosis
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Answer Key
PRE-TEST
1.
2.
3.
4.
5.
DO THIS
D
B
C
A
B
1. Remove the stuffs that are not
needed and put inside the bag
those that are important.
2. In cells, large substances are
taken in by endocytosis while
waste products are released
through exocytosis.
EXPLORE
A. 1. A particle or substance binds to receptors on the cell’s surface, stimulating
the release of pseudopodia
2. Pseudopodia surround the object until their membranes fuse, forming a
phagocytic vesicle.
3. The phagocytic vesicle pinches off from the cell membrane, entering the cell.
4. The phagocytic vesicle fuses with lysosomes, which recycle or destroy the
vesicle’s contents.
B. 1. A vesicle is formed, typically within the endoplasmic reticulum and the
Golgi apparatus or early endosomes.
2. The vesicle travels to the cell membrane.
3. The vesicle fuses to the plasma membrane, during which the two bilayers
merge.
4. The vesicle’s contents are released into the extracellular space.
PRACTICE TASK 1
1. Active
2. Exocytosis
3. True
4. Endocytosis
5. True
6. True
7. True
8. True
9. Phagocytosis
10. Endocytosis
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PRACTICE TASK 2
Endocytosis
Definition
Function
Types
Examples
Exocytosis
The process of taking in
large substance from
outside of the cell.
➢ Absorbing nutrients
for cellular function
➢ Eliminating
pathogens
➢ Disposing of
old/damaged cells
Note: There are other
possible answers
➢ Phagocytosis
➢ Pinocytosis
White blood cells engulfing
a virus and eliminating it.
Note: There are other
possible answers
The process of taking
substances outside the
cell.
➢ Removing toxins or
waste products
➢ Repairing the cell
membrane
➢ Facilitating
communication
between cells
Note: There are other
possible answers
➢ Regulated
exocytosis
➢ Constitutive
exocytosis
Note: There are other
possible answer.
Releasing a
neurotransmitter for
cellular communication.
Note: There are other
possible answers
PRACTICE TASK 3
1. Phagocytes aim to destroy pathogens by engulfing them and subjecting them to
toxic chemicals.
2. Neurotransmitters are released from synaptic vesicles into the synaptic cleft via
exocytosis.
3. Yes, endocytosis and exocytosis can occur in the same cell. It is how a cell
transport and export material in and out of the cell.
4. Exocytosis and endocytosis are important in maintaining homeostasis.
POST TEST
1. B
2. D
3. D
4. B
5. B
6. D
7. A
8. D
9. D
10. C
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References
Books
Reece, J., et.al., Campbell Biology. California: Pearson Education Inc., 2014.
Website
https://www.ck12.org/biology/cell-transport/lesson/Cell-Transport-Advanced-BIOADV/#:~:text=Cell%20transport%20refers%20to%20the,that%20they%20are%20selecti
vely%20permeable.
https://ib.bioninja.com.au/standard-level/topic-1-cell-biology/14-membranetransport/active-transport.html
http://life.nthu.edu.tw/~b830473/transmechanism.html#:~:text=It%20is%20of%20semina
l%20importance,in%20and%20out%20of%20itself.&text=Given%20the%20importance
%20of%20membrane,facilitated%20diffusion%2C%20and%20active%20transport
https://www.technologynetworks.com/immunology/articles/endocytosis-and-exocytosisdifferences-and-similarities-334059
https://courses.lumenlearning.com/suny-wmopen-biology1/chapter/endocytosis-andexocytosis/
https://www.genome.gov/genetics-glossary/Plasma-Membrane
https://biologydictionary.net/vesicle/
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