Lesson 3 | Moving Cellular Material

Student Labs and Activities Page Appropriate For:

Launch Lab 46 all students
Content Vocabulary 47 all students
Lesson Outline 48 all students
MiniLab 50 all students
Content Practice A 51
Content Practice B 52
Math Skills 53 all students
School to Home 54 all students
Key Concept Builders 55
Enrichment 59 all students
Challenge 60
Skill Practice 61 all students
Assessment
Lesson Quiz A 63
Lesson Quiz B 64

Approaching Level On Level Beyond Level English-Language Learner

Teacher evaluation will determine which activities to use or modify to meet any student’s proficiency level.

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Launch Lab LESSON 3: 5 minutes

What does the cell membrane do?

All cells have a membrane around the outside of the cell. The cell membrane separates the
inside of a cell from the environment outside a cell. What else might a cell membrane do?

Procedure
1. Read and complete a lab safety form. 3. Pour a small amount of birdseed on
2. Place a square of wire mesh on top of top of the wire mesh. Record your
a beaker. observations below.

Data and Observations

Think About This

1. What part of a cell does the wire mesh represent?

2. What happened when you poured birdseed on the wire mesh?

3. Key Concept How do you think the cell membrane affects materials that enter
and leave a cell?

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Content Vocabulary LESSON 3

Moving Cellular Material

Directions: Write the correct term in the boxes to the right of each definition. Then use the letters in the
numbered boxes to spell a seventh term.

active transport diffusion endocytosis exocytosis

facilitated diffusion osmosis passive transport

1. occurs with the help of transport

proteins

2. movement through a cell’s membrane

without using the cell’s energy

3. movement through a cell’s membrane

that requires energy

4. when a vesicle releases its contents

outside of a cell

5. movement of substances from higher

to lower concentration

6. diffusion of water molecules

7. is the process during which a cell takes in a substance by surrounding it with the cell
membrane.

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Lesson Outline LESSON 3

Moving Cellular Material

A. Passive Transport
1. A cell membrane is , which means that it allows only
certain substances to enter or leave a cell.
2. Passive transport is the movement of substances through a cell membrane without
using the cell’s .
B. Diffusion
1. Diffusion is the movement of substances from an area of
concentration to an area of
concentration.
2. Usually diffusion continues through a membrane until the
of a substance is the same on both sides of the
membrane.
C. Osmosis—The Diffusion of Water
1. Osmosis is the diffusion of molecules only through a
membrane.
2. If the concentration of water in the air surrounding a plant is less than the
concentration of water inside the plant’s vacuoles, water will diffuse into the
until the concentrations of water are equal.
3. Facilitated diffusion allows molecules to pass through a cell membrane using
proteins.
a. Carrier proteins carry through the cell membrane.
b. proteins allow ions to pass through the cell
membrane.
D. Active Transport
1. Active transport uses the cell’s to move substances
through a cell membrane.
2. Active transport moves substances from areas of
concentration to areas of concentration.

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Lesson Outline continued

3. A cell uses to take in a substance by surrounding it

with the cell membrane.
4. A cell’s vesicles release their contents outside the cell
during .
E. Cell Size and Transport
1. For a cell to survive, its surface area must be large compared to
its .
2. As a cell , its volume increases faster than its surface area.

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MiniLab LESSON 3: 20 minutes

How is a balloon like a cell membrane?

Substances within a cell are constantly in motion. How can a balloon act like a cell
membrane?

Procedure
1. Read and complete a lab safety form. 3. Use your senses to identify which
2. Make a three-column table in your substance is in each of the numbered
Science Journal to record your data. balloons.
Label the first column Balloon Number, 4. Record what you think each substance is.
the second column Substance, and the
third column Supporting Evidence. 5. Record the evidence supporting your
choice.

Analyze and Conclude

1. List the senses that were most useful in identifying the substances.

2. Infer if you could identify the substances if you were blindfolded. If so, how?

3. Describe how the substances moved and explain why they moved this way.

4. Key Concept Explain how a balloon is like a cell membrane in terms of the
movement of substances.

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Content Practice A LESSON 3

Moving Cellular Material

Directions: Complete each definition. Then use the terms below to complete the chart.

carrier proteins channel proteins diffusion endocytosis

exocytosis facilitated diffusion osmosis

Passive transport is
1.

2. 3. 4.

Active transport is
5.

6. 7.

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Content Practice B LESSON 3

Moving Cellular Material

Directions: List a fact or term next to each bullet to complete the chart.

Information to Find Answers

1. What passes through a cell using

passive transport?

2. What are three types of passive

transport?

3. How do substances move in passive

transport?

4. What is the diffusion of water

molecules only?

5. What is used in facilitated diffusion to

assist the transport of sugar and
sodium molecules?

6. What is only used in active transport?

7. How do substances move in active

transport?

8. Which proteins are used in active and

passive transport?

9. What does a cell do to a substance in

endocytosis?

10. What does a cell use to eliminate a

substance that is too large to leave by
diffusion?

11. Which structures join with the cell’s

membrane during exocytosis?

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Math Skills LESSON 3

Use Ratios
The area of a rectangle is the length times the width, or A = l × w. The surface area of a
rectangular solid is the sum of the areas of the six surfaces. The volume of this solid is the
product of the length, width, and height, or V = l × w × h. The ratio of surface area to
volume compares the amount of surface area on a three-dimensional solid to the volume
of the solid. This ratio may be expressed as A/V or A:V.
A rectangular solid measures 10 cm wide, 5 cm long, and 2 cm tall. What is
the ratio of surface area to volume?
Step 1 Calculate the surface area. Add the areas of the six surfaces.
(10 + 5) + (10 × 5) + (5 × 2) + (5 × 2) + (2 × 10) + (2 × 10) = 160 cm2
Step 2 Calculate the volume.
10 × 5 × 2 = 100 cm3
Step 3 Write the ratio. Divide by the greatest common factor to simplify.
A:V = 160:100
160 ÷ 20 = 8 and 100 ÷ 20 = 5
A/V = 8:5

Practice
1. A rectangular solid has a surface area of 3. A rectangular solid measures 5 cm long
22 cm2 and a volume of 6 cm3. What by 3 cm wide by 1 cm high. What is
is the surface-area-to-volume ratio? the surface-area-to-volume ratio?

2. A rectangular solid has a surface area of 4. A rectangular solid measures 8 cm long

52 cm2 and a volume of 24 cm3. What by 2 cm wide by 2 cm high. What is
is the surface-area-to-volume ratio? the surface-area-to-volume ratio?

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School to Home LESSON 3

Moving Cellular Material

Directions: Use your textbook to respond to each statement.

1. Use the terms below to fill in the concept map about the movement of materials into
and out of cells.

diffusion endocytosis exocytosis facilitated diffusion osmosis

Materials move in
and out of cells in
processes that

do not use the cell’s

use the cell’s energy
energy

a. c. d. e.

b.

2. With your learning partner, fill a clear drinking glass with water. Set the water on a
table. Then carefully add 1 drop of food coloring to the water. Do not mix or stir
the water. Observe the water for 5 minutes while the dye diffuses. Record your
observations here.

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Key Concepts Builder LESSON 3

Moving Cellular Material

Key Concept How do materials enter and leave cells?
Directions: Write a short description of how each transport system works. Under each description, add a simple
diagram that shows how the process occurs in a cell. Include arrows.

Passive Transport
Diffusion Osmosis Facilitated Diffusion
Description: Description: Description:

Diagram: Diagram: Diagram:

Active Transport

Endocytosis Exocytosis
Description: Description:

Diagram: Diagram:

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Key Concepts Builder LESSON 3

Moving Cellular Material

Key Concept How do materials enter and leave cells?
Directions: On each line, write the term from the word bank that correctly completes each sentence. Each term is
used only once.

1. the movement of substances from an area of A. semipermeable

higher concentration to an area of lower
concentration B. passive transport

2. transport proteins that carry large molecules, such C. diffusion

as sugar molecules, through a cell membrane D. equilibrium
3. the state a substance is in when the E. osmosis
concentration of the substance is the same on
both sides of a cell membrane F. facilitated diffusion
4. when a cell takes in a substance by surrounding G. transport proteins
it with the cell membrane
H. carrier proteins
5. the diffusion of water molecules only
I. channel proteins
6. when molecules pass through a cell membrane
using special proteins J. active transport

7. transport proteins that form pores through a cell K. endocytosis

membrane L. exocytosis
8. the movement of substances through a cell
membrane by using the cell’s energy
9. proteins that assist with the transport of
molecules through a cell membrane
10. when a cell’s vesicles release their contents
outside the cell
11. what a cell membrane is because it allows only
certain substances to enter or leave a cell
12. the movement of substances through a cell
membrane without using the cell’s energy

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Key Concepts Builder LESSON 3

Moving Cellular Material

Key Concept How do materials enter and leave cells?
Directions: Answer each question on the lines provided. Use complete sentences.

1. What is active transport?

2. What is endocytosis?

3. What is exocytosis?

4. How does a cell use endocytosis to form a vesicle?

5. How does a cell use exocytosis to release the contents of a vesicle outside the cell?

6. What role does cellular energy play in active transport?

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Key Concepts Builder LESSON 3

Moving Cellular Material

Key Concept How does cell size affect the transport of materials?

Relationship Between Surface Area and Volume

Surface Area 6 24 54
Volume 1 8 27

Ratio of Surface Area to Volume 6 to 1 3 to 1 2 to 1

Directions: The table above shows the surface area and volume of sample objects. Use the table to help answer
each question. Use complete sentences.

1. What happens to the volume of an object as its surface area increases?

2. What is the changing relationship between volume and surface area as an object
gets bigger?

3. What problem would unlimited cell growth pose for a cell?

4. Why can a cell not survive under conditions of unlimited growth?

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Enrichment LESSON 3

Understanding Alzheimer’s Disease

Imagine slowly losing your most have several functions, one of which is to
precious memories. You can barely help transport materials inside cells.
remember how to do the simplest task, let Scientists are studying several proteins in
alone recognize the face of a loved one. nerve cells, including the amyloid
This devastating scenario is common for precursor protein (APP). The exact role of
the nearly 5 million Americans afflicted APP is unclear, but it appears to be crucial
with Alzheimer’s disease. This progressive in transporting materials and information
brain disease attacks nerve cells in the from the nerve cell to the axons. In
brain, usually in older people. It affects a patients with Alzheimer’s disease, this cell
person’s memory, thinking patterns, and transport system breaks down. As a result,
behavior. In the United States, Alzheimer’s the cell sends out signals that eventually
is the sixth leading cause of death. lead to its death.
Currently, there is no cure.
Working Toward a Cure
Cell Transport and Alzheimer’s Disease Scientists are working to understand how
Scientists have made great strides in this transport breakdown occurs. They have
understanding Alzheimer’s disease. They discovered an enzyme that splits APP into
now know that certain genes have a role two parts, one of which is called beta
in the disease. Recently, they also amyloid. When this split occurs in a certain
discovered that Alzheimer’s might be way, beta amyloid forms the plaques, or
linked to problems associated with cell deposits of protein, found in and around the
transport. Nerve cells have axons that can nerve cells of Alzheimer’s patients. By
extend several feet from the main body of regulating the production of beta amyloid,
the cell, which makes transport an scientists hope to prevent the formation of
important issue. plaques and halt the death of nerve cells in
As you have learned, proteins are one the brain. The challenge, however, lies in
type of macromolecule in cells. Proteins keeping all the other functions of APP intact.

Applying Critical-Thinking Skills

Directions: Answer each question or respond to each statement.

1. Infer what it means when a disease is called progressive.

2. Identify the challenges that scientists face in their search for a cure for
Alzheimer’s disease.
3. Evaluate the information in the article. What does it imply about the importance
of cell transport?

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Challenge LESSON 3

Observing Cell Transport

Using simple materials you have in your home, devise an experiment that will allow you
to observe cell transport. Develop a specific question that your experiment will answer. Be
sure to list materials that you use and develop the appropriate steps when you conduct your
experiment. Which safety precautions should you consider while you plan and perform
your experiment?
Prepare a report detailing your question, experimental plans, and procedures, data, and
results, as well as your conclusions.

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Skill Practice Analyze and Conclude LESSON 3: 30 minutes

How does an object’s size affect the transport

of materials?
Nutrients, oxygen, and other materials enter and leave a cell through the cell membrane.
Does the size of a cell affect the transport of these materials throughout the cell? In this lab,
you will analyze and conclude how the size of a cube of egg white affects material
transport.

Learn It
To analyze how an object’s size affects material transport, you will need to calculate each
object’s surface-area-to-volume ratio. The following formulas are used to calculate surface
area and volume of a cube.
surface area (mm2) = (length of 1 side)2 × 6
volume (mm3) = (length of 1 side)3
To calculate the ratio of surface area to volume, divide surface area by volume.
Materials
hard-cooked eggs 250-mL beaker plastic knife blue food coloring
metric ruler plastic spoon paper towels

Safety
Try It
1. Read and complete a lab safety form.
2. Measure and cut one large cube of egg white that is 20 mm on each side. Then,
measure and cut one small cube of egg white that is 10 mm on each side.
3. Place 100 mL of water in a plastic cup. Add 10 drops of food coloring. Gently add the
egg-white cubes and soak overnight.
4. Remove the cubes from the cup with a plastic spoon and place them on a paper towel.
Cut each cube in half.
5. Examine the inside surface of each cube. Measure and record in millimeters how deep the
blue food coloring penetrated into each cube.
Large cube:
Small cube:

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Skill Practice continued

Apply It
6. How does the depth of the color compare on the two cubes?

7. Calculate the surface area, the volume, and the surface-area-to volume ratio of each
cube. How do the surface-area-to-volume ratios of the two cubes compare?

8. Key Concept Would a cell with a small surface-area-to-volume ratio be able to

transport nutrients and waste through the cell as efficiently as a cell with a large
surface-area-to-volume ratio?

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Lesson Quiz A LESSON 3

Moving Cellular Material

Multiple Choice
Directions: On the line before each question, write the letter of the correct answer.

1. Which function diffuses water molecules?

A. osmosis
B. endocytosis
C. passive transport
2. Which function moves substances from a lower concentration to a higher
concentration?
A. osmosis
B. diffusion
C. active transport
3. What happens as a cell gets bigger?
A. Its volume decreases.
B. Its surface area increases.
C. Its need for nutrients decreases.

Matching
Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is
used only once.

4. when a cell takes in a substance by

surrounding it with its cell membrane
A. active

5. when a cell eliminates large substances by B. passive

releasing them from vesicles into the area C. endocytosis
outside the cell
D. exocytosis
6. requiring energy
E. size
7. limited by the ratio of its surface area to its
volume
8. an example is facilitated diffusion

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Lesson Quiz B LESSON 3

Moving Cellular Material

Completion
Directions: On each line, write the term that correctly completes each sentence.

1. The diffusion of water molecules is called .

2. During active transport, materials move from an area of
concentration to an area of concentration.
3. A cell’s size is limited by its ratio.
4. is when a cell takes in substances by engulfing them with
its cell membrane.
5. The process of occurs when a cell’s vesicles release their
contents outside the cell.

Short Answer
Directions: Respond to each statement on the lines provided.

6. Compare and contrast active transport and passive transport.

7. Relate the reason why a large cell is less able to move nutrients and wastes than
a small cell.

8. Distinguish between the two kinds of proteins involved in facilitated diffusion.

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