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Chapter 4
The Cell in Action
Table of Contents
Section 1 Exchange with the Environment
Section 2 Cell Energy
Section 3 The Cell Cycle
Chapter 4
Section 1 Exchange with the
Environment
Bellringer
Which of the following best describes a living cell:
a) building block
b) a living organism
c) a complex factory
d) all of the above
Write a paragraph in your science notebook defending
your choice.
Chapter 4
Section 1 Exchange with the
Environment
Objectives
• Explain the process of diffusion.
• Describe how osmosis occurs.
• Compare passive transport with active transport.
• Explain how large particles get into and out of cells.
Chapter 4
Section 1 Exchange with the
Environment
What Is Diffusion?
• Diffusion is the movement of particles from regions of
higher density to regions of lower density.
• Diffusion of Water The diffusion of water through cell
membranes is called osmosis.
Chapter 4
Section 1 Exchange with the
Environment
What Is Diffusion?, continued
• The Cell and Osmosis
• Osmosis is important
to cell functions.
• Plasma surrounds red blood cells and is made up of
water, salts, sugars, and other particles. Osmosis
keeps the concentration of these particles in balance.
• When a wilted plant is watered, osmosis makes the
plant firm again.
Chapter 4
Section 1 Exchange with the
Environment
 Water and dissolved substances diffuse
into and out of the cell at the same rate.
Plant Cell
Blood Cell
11,397x
Chapter 4
Section 1 Exchange with the
Environment
 Solute concentration is higher inside the cell.
 Water diffuses into the cell.
Plant Cell
Blood Cell
13,000x
Chapter 4
Section 1 Exchange with the
Environment
 Solute concentration is higher outside the
cell.
 Water diffuses out of the cell.
Plant Cell
Blood Cell
13,000x
Chapter 4
Section 1 Exchange with the
Environment
Reading Check: Why would red blood cells
burst if you placed them in pure water?
 Red blood cells would burst in pure water
because water particles move from outside,
where particles were dense, to inside the cell,
where particles were less dense. This
movement of water would cause red blood
cells to fill up and burst.
Chapter 4
Section 1 Exchange with the
Environment
Moving Small Particles
• Passive Transport The movement of particles across
a cell membrane without the use of energy by the cell
is called passive transport.
• Active Transport A process of transporting particles
that requires the cell to use energy is called active
transport.
Chapter 4
Section 1 Exchange with the
Environment
Chapter 4
Section 1 Exchange with the
Environment
Moving Large Particles
• Endocytosis The active-transport process by which
a cell surrounds a large particle and encloses the
particle in a vesicle to bring the particle into the cell
is called endocytosis.
• Exocytosis The active-transport process in which a
cell releases a particle by enclosing the particle in a
vesicle that then moves to the cell surface and fuses
with the cell membrane is called exocytosis.
Chapter 4
Section 1 Exchange with the
Environment
Chapter 4
Section 1 Exchange with the
Environment
QUICK CHECK QUIZ!!!
1. What part of a cell do materials pass
through to get into and out of the cell?
the cell membrane
2. What is osmosis?
the diffusion of water through the semipermeable cell membrane
Chapter 4
Section 1 Exchange with the
Environment
QUICK CHECK QUIZ!!!
3. Describe how each of the following would
get through a cell membrane and into a
cell? Which require active transport?
– pure water
– sugar entering a cell that already contains a
high concentration of particles
– sugar entering a cell that has a low
concentration of particles
– a large protein
Chapter 4
Section 1 Exchange with the
Environment
Section 4.1 Review
• Diffusion is the movement of particles from
an area of high concentration to an area of
low concentration.
• Osmosis is the diffusion of water through a
semi-permeable membrane.
Chapter 4
Section 1 Exchange with the
Environment
Section 4.1 Review
• Cells move small particles by diffusion, which
is an example of passive transport, and by
active transport.
Chapter 4
Section 1 Exchange with the
Environment
Section 4.1 Review
• Large particles enter the cell by endocytosis,
and exit the cell by exocytosis.
Chapter 4
Section 2 Cell Energy
Bellringer
Make a list of all the different types of cells that
you can think of and the jobs they do. Then make
a list of all the reasons that a cell needs energy.
Write your answers in your science notebook.
Chapter 4
Section 2 Cell Energy
Objectives
• Describe photosynthesis and cellular respiration.
• Compare cellular respiration with fermentation.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 4
Section 2 Cell Energy
From Sun to Cell
• Photosynthesis is the process a plant uses to
create glucose.
Chapter 4
Section 2 Cell Energy
From Sun to Cell
• Chlorophyll Plant cells have molecules that absorb
light energy. These molecules are called pigments.
Chlorophyll, the main pigment used in
photosynthesis, gives plants their green color.
Chapter 4
Section 2 Cell Energy
Getting Energy from Food
• Cellular Respiration During cellular respiration, food
(such as glucose) is broken down into carbon dioxide
and water, and energy is released.
Chapter 4
Section 2 Cell Energy
Reading Check: What is the difference between
cellular respiration and breathing?
Cellular respiration is a chemical
process by which cells produce energy from
food. Breathing supplies the body with the raw
materials needed for cellular respiration.
Chapter 4
Section 2 Cell Energy
How do cells communicate
with each other?
By cell phone, of course!!!
Chapter 4
Section 2 Cell Energy
Getting Energy from Food, continued
• Connection Between Photosynthesis and Respiration
During photosynthesis, cells take in carbon dioxide
and release oxygen. During cellular respiration, cells
use oxygen to break down glucose and release energy
and carbon dioxide.
Chapter 4
Section 2 Cell Energy
Chapter 4
Section 2 Cell Energy
Getting Energy from Food, continued
Fermentation is the breakdown of food without the
use of oxygen. When muscles can’t get the oxygen for
cellular respiration, they use fermentation to get
energy.
Chapter 4
Section 2 Cell Energy
Reading Check: What are two kinds of
fermentation?
The kind that happens in muscle cells
of animals and the kind that occurs in
bacteria.
Chapter 4
Section 2 Cell Energy
QUICK CHECK QUIZ!!!
TRUE OR FALSE?
1. Plants and animals capture their energy from the
sun.
FALSE!!!
2. Cellular respiration describes how a cell breathes.
FALSE!!!
3. Fermentation produces ATP and lactic acid.
TRUE!!!
Chapter 4
Section 2 Cell Energy
Section 4.2 Review
• Most of the energy that fuels life processes
comes from the sun.
• The sun’s energy is converted into food by
the process of photosynthesis.
• Cellular respiration breaks down glucose into
water, carbon dioxide, and energy.
• Fermentation is a way that cells get energy
from their food without using oxygen.
Chapter 4
Section 3 The Cell Cycle
Bellringer
Biology is the only science in which multiplication
means the same thing as division—at least with
regards to cells.
Explain what is meant by this statement in your
science notebook.
Chapter menu
Resources
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 4
Section 3 The Cell Cycle
Objectives
• Explain how cells produce more cells.
• Describe the process of mitosis.
• Explain how cell division differs in animals and plants.
Chapter 4
Section 3 The Cell Cycle
The Life of a Cell
The cell cycle is
the life stages of
a cell. The cell
cycle begins
when the cell is
formed and
ends when the
cell divides and
forms new cells.
Chapter 4
Section 3 The Cell Cycle
The Life of a Cell
Before a cell divides, it must make a copy of its
DNA which is organized into structures called
chromosomes. Chromosomes are containers
for DNA, the hereditary material that controls
cell activities.
Chapter 4
Section 3 The Cell Cycle
Making More Prokaryotic Cells Cell division in bacteria is
called binary fission, which means “splitting into two parts.”
Bacteria have a single circular DNA molecule (chromosome).
Binary fission results in two cells that each contain one copy
of the circle of DNA.
Chapter 4
Section 3 The Cell Cycle
The Life of a Cell, continued
• Eukaryotic Cells and Their
DNA The chromosomes
of eukaryotic cells contain
more DNA than those of
prokaryotic cells.
• In a eukaryotic cell,
chromosomes are found in
the nucleus and are made of
DNA and protein.
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 4
Section 3 The Cell Cycle
The Life of a Cell, continued
• Pairs of
similar
chromosomes
are called
homologous
chromosomes.
Copyright © by Holt, Rinehart and Winston. All rights reserved.
Chapter 4
Section 3 The Cell Cycle
The Life of a Cell, continued
Making More Eukaryotic Cells
The cell cycle has three stages:
1. Interphase: The cell grows and copies its
chromosomes. The two copies are now called
chromatids.
2. Mitosis: The process of chromosome separation.
3. Cytokinesis: The cell splits into two identical cells.
Chapter 4
Section 3 The Cell Cycle
Mitosis and the Cell Cycle
• Mitosis has four phases:
1. prophase
2. metaphase
3. anaphase
4. telophase
Chapter 4
Section 3 The Cell Cycle
Mitosis and the Cell Cycle, continued
• Cytokinesis is the
division of cytoplasm.
• In animal cells and
other eukaryotes that
do not have cell walls,
division of the
cytoplasm begins at
the cell membrane.
Chapter 4
Section 3 The Cell Cycle
Mitosis and the Cell Cycle, continued
• In plant cells
and in other
eukaryotes with
cell walls, a cell
plate forms and
the cell splits
into two cells.
Chapter 4
Section 3 The Cell Cycle
Chapter 4
Section 2 The Cell Cycle
Section 4.2
4.3 Review
Review
Section
1. A cell produces more cells by first copying its DNA.
2. Eukaryotic cells produce more cells through the four
phases of mitosis.
3. Mitosis produces two cells that have the same number of
chromosomes as the parent cell.
4. At the end of mitosis, a cell divides the cytoplasm by
cytokinesis.
5. In plant cells, a cell plate forms between the two new
cells during cytokinesis.
Chapter 4
The Cell in Action
Concept Map
Use the terms below to complete the concept map on
the next slide.
ATP
photosynthesis
oxygen
water
consumers
lactic acid
producers
respiration
energy
Chapter 4
Concept Map
Chapter 4
Concept Map
End of Chapter 4 Show
Chapter 4
Standardized Test Preparation
Reading
Read each of the passages. Then, answer the
questions that follow each passage.
Chapter 4
Standardized Test Preparation
Passage 1 Perhaps you have heard that jogging or
some other kind of exercise “burns” a lot of Calories.
The word burn is often used to describe what happens
when your cells release stored energy from food. The
burning of food in living cells is not the same as the
burning of logs in a campfire. When logs burn, the
energy stored in wood is released as thermal energy
and light in a single reaction. But this kind of reaction is
not the kind that happens in cells. Instead, the energy
that cells get from food molecules is released at each
step of a series of chemical reactions.
Chapter 4
Standardized Test Preparation
1. According to the passage, how do cells release
energy from food?
A in a single reaction
B as thermal energy and light
C in a series of reactions
D by burning
Chapter 4
Standardized Test Preparation
1. According to the passage, how do cells release
energy from food?
A in a single reaction
B as thermal energy and light
C in a series of reactions
D by burning
Chapter 4
Standardized Test Preparation
2. Which of the following statements is a fact in the
passage?
F Wood burns better than food does.
G Both food and wood have stored energy.
H Food has more stored energy than wood does.
I When it is burned, wood releases only thermal
energy.
Chapter 4
Standardized Test Preparation
2. Which of the following statements is a fact in the
passage?
F Wood burns better than food does.
G Both food and wood have stored energy.
H Food has more stored energy than wood does.
I When it is burned, wood releases only thermal
energy.
Chapter 4
Standardized Test Preparation
3. According to the passage, why might people be
confused between what happens in a living cell and
what happens in a campfire?
A The word burn may describe both processes.
B Thermal energy is released during both processes.
C Wood can be burned and broken down by living
cells.
D Jogging and other exercises use energy.
Chapter 4
Standardized Test Preparation
3. According to the passage, why might people be
confused between what happens in a living cell and
what happens in a campfire?
A The word burn may describe both processes.
B Thermal energy is released during both processes.
C Wood can be burned and broken down by living
cells.
D Jogging and other exercises use energy.
Chapter 4
Standardized Test Preparation
Passage 2 The word respiration means “breathing,”
but cellular respiration is different from breathing.
Breathing supplies your cells with the oxygen that
they need for cellular respiration. Breathing also rids
your body of carbon dioxide, which is a waste product
of cellular respiration. Cellular respiration is the
chemical process that releases energy from food.
Continued on the next slide
Chapter 4
Standardized Test Preparation
Passage 2, continued Most organisms obtain energy
from food through cellular respiration. During cellular
respiration, oxygen is used to break down food
(glucose) into CO2 and H2O, and energy is released.
In humans, most of the energy released is used to
maintain body temperature.
Chapter 4
Standardized Test Preparation
1. According to the passage, what is glucose?
A a type of chemical process
B a type of waste product
C a type of organism
D a type of food
Chapter 4
Standardized Test Preparation
1. According to the passage, what is glucose?
A a type of chemical process
B a type of waste product
C a type of organism
D a type of food
Chapter 4
Standardized Test Preparation
2. According to the passage, how does cellular
respiration differ from breathing?
F Breathing releases carbon dioxide, but cellular
respiration releases oxygen.
G Cellular respiration is a chemical process that uses
oxygen to release energy from food, but breathing
supplies cells with oxygen.
H Cellular respiration requires oxygen, but breathing
does not.
I Breathing rids your body of waste products, but
cellular respiration stores wastes.
Chapter 4
Standardized Test Preparation
2. According to the passage, how does cellular
respiration differ from breathing?
F Breathing releases carbon dioxide, but cellular
respiration releases oxygen.
G Cellular respiration is a chemical process that uses
oxygen to release energy from food, but breathing
supplies cells with oxygen.
H Cellular respiration requires oxygen, but breathing
does not.
I Breathing rids your body of waste products, but
cellular respiration stores wastes.
Chapter 4
Standardized Test Preparation
3. According to the passage, how do humans use
most of the energy released?
A to break down food
B to obtain oxygen
C to maintain body temperature
D to get rid of carbon dioxide
Chapter 4
Standardized Test Preparation
3. According to the passage, how do humans use
most of the energy released?
A to break down food
B to obtain oxygen
C to maintain body temperature
D to get rid of carbon dioxide
Chapter 4
Standardized Test Preparation
Interpreting Graphics
The graph below shows the cell cycle. Use this graph
to answer the questions that follow.
Chapter 4
Standardized Test Preparation
1. Which part of the cell
cycle lasts longest?
A interphase
B mitosis
C cytokinesis
D There is not enough
information to determine the
answer.
Chapter 4
Standardized Test Preparation
1. Which part of the cell
cycle lasts longest?
A interphase
B mitosis
C cytokinesis
D There is not enough
information to determine the
answer.
Chapter 4
Standardized Test Preparation
2. Which of the following lists
the parts of the cell cycle in
the proper order?
F mitosis, cytokinesis, mitosis
G interphase, cytokinesis,
mitosis
H interphase, mitosis,
interphase
I mitosis, cytokinesis,
interphase
Chapter 4
Standardized Test Preparation
2. Which of the following lists
the parts of the cell cycle in
the proper order?
F mitosis, cytokinesis, mitosis
G interphase, cytokinesis,
mitosis
H interphase, mitosis,
interphase
I mitosis, cytokinesis,
interphase
Chapter 4
Standardized Test Preparation
3. Which part of mitosis is
the briefest?
A interphase
B cell cycle
C cytokinesis
D There is not enough
information to determine
the answer.
Chapter 4
Standardized Test Preparation
3. Which part of mitosis is
the briefest?
A interphase
B cell cycle
C cytokinesis
D There is not enough
information to determine
the answer.
Chapter 4
Standardized Test Preparation
4. Why is the cell cycle represented
by a circle?
F The cell cycle is a continuous
process that begins again after it
finishes.
G The cell cycle happens only in
cells that are round.
H The cell cycle is a linear process.
I The cell is in interphase for more
than half of the cell cycle.
Chapter 4
Standardized Test Preparation
4. Why is the cell cycle represented
by a circle?
F The cell cycle is a continuous
process that begins again after it
finishes.
G The cell cycle happens only in
cells that are round.
H The cell cycle is a linear process.
I The cell is in interphase for more
than half of the cell cycle.
Chapter 4
Standardized Test Preparation
Math
Read each question, and choose the best answer.
Chapter 4
Standardized Test Preparation
1. A normal cell spends 90% of its time in interphase.
How is 90% expressed as a fraction?
A 3/4
B 4/5
C 85/100
D 9/10
Chapter 4
Standardized Test Preparation
1. A normal cell spends 90% of its time in interphase.
How is 90% expressed as a fraction?
A 3/4
B 4/5
C 85/100
D 9/10
Chapter 4
Standardized Test Preparation
2. If a cell lived for 3 weeks and 4 days, how many
days did it live?
F7
G 11
H 21
I 25
Chapter 4
Standardized Test Preparation
2. If a cell lived for 3 weeks and 4 days, how many
days did it live?
F7
G 11
H 21
I 25
Chapter 4
Standardized Test Preparation
3. How is 2  3  3  3  3 expressed in exponential
notation?
A 3  24
B 2  33
C 34
D 2  34
Chapter 4
Standardized Test Preparation
3. How is 2  3  3  3  3 expressed in exponential
notation?
A 3  24
B 2  33
C 34
D 2  34
Chapter 4
Standardized Test Preparation
4. Cell A has 3 times as many chromosomes as cell B
has. After cell B’s chromosomes double during
mitosis, cell B has 6 chromosomes. How many
chromosomes does cell A have?
F3
G6
H9
I 18
Chapter 4
Standardized Test Preparation
4. Cell A has 3 times as many chromosomes as cell B
has. After cell B’s chromosomes double during
mitosis, cell B has 6 chromosomes. How many
chromosomes does cell A have?
F3
G6
H9
I 18
Chapter 4
Standardized Test Preparation
5. If x  2  3, what does x  1 equal?
A4
B3
C2
D1
Chapter 4
Standardized Test Preparation
5. If x  2  3, what does x  1 equal?
A4
B3
C2
D1
Chapter 4
Standardized Test Preparation
6. If 3x  2  26, what does x  1 equal?
F7
G8
H9
I 10
Chapter 4
Standardized Test Preparation
6. If 3x  2  26, what does x  1 equal?
F7
G8
H9
I 10
Chapter 4
Section 1 Exchange with the
Environment
Chapter 4
Section 2 Cell Energy
Chapter 4
Section 2 Cell Energy
Chapter 4
Standardized Test Preparation