Download Unit 3 Bioenergetics: Cellular Respiration and Photosynthesis

Unit 3 Bioenergetics: Cellular Respiration and
Photosynthesis
Keystone Assessment Anchors
BIO.A.3.1.1. Describe the fundamental roles of plastids (e.g., chloroplasts) and mitochondria in energy
transformations.
BIO.A.3.2.1.Compare the basic transformation of energy during photosynthesis and cellular respiration.
BIO.A.3.2.2.Describe the role of ATP in biochemical reactions.
Unit Objectives
Essential Question
Describe the structure of mitochondria and
chloroplasts in eukaryotic cells.
How do organisms obtain and use
energy to carry out their life functions?
Describe the fundamental roles of plastids
and mitochondria in energy
transformations.
Compare the basic transformations of
energy during photosynthesis and cellular
respiration.
Unit 3 Bioenergetics – Cellular Respiration and Photosynthesis
3.1 Cell Structures Involved in Processing Energy
3.2 Energy Transformations in the Cell
Describe the structure of ATP.
3.3 ATP
Describe the role of ATP in biochemical
reactions.
3.4 Photosynthesis
3.5 Cellular Respiration
3.6 Review Bioenergetics
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Unit 3 : Bioenergetics : Overview of Cell Structures
The Plasma Membrane
1. The barrier between the cytoplasm inside the cell and the environment outside the cell
is the ____________________ ____________________.
2. The plasma membrane is composed of phospholipids arranged in two layers known as a
________________________ ______________________.
3. Label the phospholipid diagram below.
__________________ loves water (__________________)
____________________ hates water (___________________)
4. Molecules that are hydrophobic can easily ___________ _________________ the
membrane because they are water-hating like the interior of the membrane.
5. There are other molecules in the plasma membrane. For instance, molecules of
____________________________ help the plasma membrane keep its shape.
Cytoplasm and Cytoskeleton
6. List three functions of the cytoplasm.
Nucleus
7. _________________ is the cell’s control center.
Mitochondria
8. _________________the power plants of the cell.
9. They use glucose to make molecules of __________ which is an energy-carrying
molecule that is used inside cells for energy.
10. Some scientists think that _________________________ were once free-living and were
engulfed (taken in) by other prokaryotic cells. The two organisms evolved a relationship
that benefitted both. This theory is called the ___________________________
______________.
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Endoplasmic reticulum
11. Name the two types of endoplasmic reticulum.
12. What is the difference between them?
Ribosomes
13. The place where ribosomes are made is the __________________________.
14. The contain the nucleic acid of ________________.
15.
Golgi Apparatus
16. The Golgi apparatus processes ________________ and prepares them for use both
___________________ and _____________________ the cell.
Vesicles and Vacuoles
17. Vesicles and vacuoles ______________ and _____________________ materials in the
cell.
18. List the other two types of vesicles and explain what they do.
Centrioles
19. Centrioles assures that new cells have a _____________________ number of
chromosomes after the cell divides.
Special Structures in Plant Cells
20. Explain the function of each of the following structures found in plant cells.
Cell Wall –
Central Vacuole –
Plastids –
Chloroplasts –
Chromoplasts –
Leukoplasts -
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Lesson 3.2: Critical Reading
Name___________________ Class______________ Date________
Read these passages from the text and answer the questions that follow.
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 (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.
The phospholipid bilayer consists of two layers of phospholipids (left), with a hydrophobic, or waterhating, interior and a hydrophilic, or water-loving, exterior. A single phospholipid molecule is depicted
on the right.
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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
1. What is the plasma membrane?
2. What is the meaning of semipermeability?
3. Discuss why the plasma membrane must be a bilayer.
4. What are some of the “other” molecules in the plasma membrane? Describe their function.
5. What are cilia and flagella?
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Lesson 3.2 : Multiple Choice
Name ___________________________________________
Circle the letter of the correct choice.
1. The power plant of the cell is the
a. Nucleus
b. ribosome
Period ___________
c. chloroplast
d. mitochondria
2. Which organelle ensures that after cell division each daughter has the correct number of
chromosomes?
a. The nucleus
b. the endoplasmic reticulum c. the centriole d. the cytoskeleton
3. Structures specific in plant cells but not in animal cells include
a. A large central vacuole b. the mitochondria c. the cell membrane
d. cytoplasts
4. Having tissues that digest food, such as in the jellyfish, is an example of
a. Cell-level organization
c. organ-level organization
b. Tissue-level organization
d. organ system-level organization
5. The plasma membrane contains which of the following?
a. Phospholipids b. cholesterol molecules c. many proteins
d. all of the above
6. Which of the following is true of the nucleus?
a. The nucleus is considered the control center of the cell.
b. The nucleus contains all the cell’s DNA.
c. All cells have a nucleus.
d. All of the above.
7. Which structure determines what molecules can enter and leave the cell?
a. The plasma membrane b. the cell wall c. the nucleus d. all of the above
8. Which organelle may have allowed early eukaryotes to make food and produce oxygen?
a. The Golgi apparatus
b. the central vacuole c. the plastids d. the cell wall
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Lesson 3.2: Vocabulary II
Fill in the blank with the appropriate term.
1. The ____________ is often considered to be the cell’s control center.
2. The ____________ consists of everything inside the plasma membrane of the cell.
3. The plasma membrane forms a ____________ between the inside and outside of the cell.
4. The ____________ is essentially a “skeleton” inside the cell.
5. The rough endoplasmic reticulum is covered with ____________.
6. Lysosomes use ____________ to break down foreign matter and dead cells.
7. ____________ cells specifically have a cell wall, a large central vacuole, and chloroplasts.
8. The endoplasmic reticulum is an organelle that helps make and transport ____________ and
lipids.
9. Mitochondria are sometimes referred to as the ____________ of the cell
10. Human beings have ____________-level organization, in which groups of organs work
together to do a certain job.
11. Centrioles help make sure each daughter cell has the correct number of ____________
after the cell divides.
12. Cilia and ____________ are extensions of the plasma membrane of many cells.
Terms
a. barrier
i. plant cells
b. chromosomes
j. powerhouse
c. cytoplasm
k. proteins
d. cytoskeleton
i. ribosomes
e. flagella
f. lysosomes
g. nucleus
h. organ-system
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Name _______________________________________Class/Period_______________________________
Plasmodesmata
Lysosome
Vacuoles
Cilia
Trichocyst
Mitochondria
Middle lamella
Golgi apparatus
Plastid
Cell wall
Endoplasmic reticulum
Flagella
Glycocalyx
Peroxisome
Nucleus
Cell membrane
First Round
Second Round
Semifinals
Finals
Winner
Rules
1.‑First Round — Cell feature found inside
the cell wins.
2.‑Second Round — The winner is not
visible with 400X magnification.
3.‑Semifinals — Cell feature discovered
using analytical cell fractionation wins.
4.‑Finals — The winner self-replicates!
Sweet 16 Cell Biology Tournament
© 2012, Flinn Scientific, Inc. All Rights Reserved. Reproduced for one-time use with permission from Flinn Scientific, Inc. Batavia, Illinois, U.S.A. No part of this material may be reproduced or
transmitted in any form or by any means, electronic or mechanical, including, but not limited to photocopy, recording, or any information storage and retrieval system, without permission in writing
from Flinn Scientific, Inc.
© 2008 Flinn Scientific, Inc. All Rights Reserved.
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C HAPTER
4
Photosynthesis and
Cellular Respiration Worksheets
Chapter Outline
4.1
E NERGY FOR L IFE
4.2
P HOTOSYNTHESIS : S UGAR AS F OOD
4.3
P OWERING THE C ELL: C ELLULAR R ESPIRATION
4.4
ANAEROBIC R ESPIRATION
Image copyright Jacob Hamblin, 2014. www.shutterstock.com. Used under license from Shutterstock.com.
•
•
•
•
Lesson 4.1: Energy for Life
Lesson 4.2: Photosynthesis: Sugar as Food
Lesson 4.3: Powering the Cell: Cellular Respiration
Lesson 4.4: Anaerobic Respiration
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4.1. Energy for Life
4.1 Energy for Life
Lesson 4.1: True or False
Name
Class
Date
Write true if the statement is true or false if the statement is false.
1. All life needs energy.
2. C6 H12 O6 + 6O2 → 6CO2 + 6H2 O is the chemical reaction of photosynthesis.
3. Glucose is a carbohydrate that stores chemical energy in a concentrated and stable form.
4. Many scientists consider photosynthesis to be the most important life process on Earth.
5. Only autotrophs can perform photosynthesis.
6. Only four types of organisms —plants, algae, fungi and some bacteria —can make food through photosynthesis.
7. ATP is the “energy currency” of the cell, so it makes sense that a molecule of ATP contains much more
chemical energy than a molecule of glucose.
8. Whereas photosynthesis occurs in only some organisms, cellular respiration occurs in the cells of all living
things.
9. Like matter, energy is also recycled by living organisms.
10. Heterotrophs cannot make their own food.
11. Because you are able to cook your own food in the microwave oven, you are a producer.
12. As mushrooms are fungi, they are heterotrophs.
13. A food chain shows how energy and matter flow from consumers to producers.
14. Photosynthetic animals are autotrophs.
15. Autotrophs are producers.
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.1: Critical Reading
Name
Class
Date
Read these passages from the text and answer the questions that follow.
Introduction
All living things need energy, which is defined as the ability to do work. You can often see energy at work in living
things —a bird flies through the air, a firefly glows in the dark, a dog wags its tail. These are obvious ways that living
things use energy, but living things constantly use energy in less obvious ways as well.
Why Living Things Need Energy
Inside every cell of all living things, energy is needed to carry out life processes. Energy is required to break down
and build up molecules and to transport molecules across plasma membranes. All life’s work needs energy. A lot
of energy is also simply lost to the environment as heat. The story of life is a story of energy flow —its capture, its
change of form, its use for work, and its loss as heat. Energy, unlike matter, cannot be recycled, so organisms require
a constant input of energy. Life runs on chemical energy. Where do living organisms get this chemical energy?
How Organisms Get Energy: Autotrophs and Heterotrophs
The chemical energy that organisms need comes from food. Food consists of organic molecules that store energy
in their chemical bonds. In terms of obtaining food for energy, there are two types of organisms: autotrophs and
heterotrophs.
Autotrophs
Autotrophs are organisms that make their own food. Most autotrophs use the energy in sunlight to make food in a
process called photosynthesis. Only three types of organisms —plants, algae, and some bacteria —can make food
through photosynthesis.
Autotrophs are also called producers. They produce food not only for themselves but for all other living things as
well (which are known as consumers). This is why autotrophs form the basis of food chains.
Heterotrophs
Heterotrophs are living things that cannot make their own food. Instead, they get their food by consuming other
organisms, which is why they are also called consumers. They may consume autotrophs or other heterotrophs.
Heterotrophs include all animals and fungi and many single-celled organisms. What do you think would happen to
consumers if all producers were to vanish from Earth?
Questions
1. What is energy? Give an example of how energy is used in a living organism.
2. Distinguish between autotrophs and heterotrophs.
3. Determine if the following are autotrophs or heterotrophs: (a) a giant redwood tree, (b) a spider, (c) a rose bush,
(d) a mushroom, (e) a blue whale.
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4.1. Energy for Life
4. Distinguish between autotrophs and heterotrophs.
5. Determine if the following are autotrophs or heterotrophs: (a) a giant redwood tree, (b) a spider, (c) a rose bush,
(d) a mushroom, (e) a blue whale
6. How is energy used in a cell?
7. Why are autotrophs considered the basis of food chains?
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.1: Multiple Choice
Name
Class
Date
Circle the letter of the correct choice.
1. Photosynthesis
a.
b.
c.
d.
uses the energy in sunlight to make food.
uses the glucose in sunlight to make food.
uses the energy in sunlight to make ATP.
breaks down glucose to form ATP.
2. Which of the following autotrophs is also a producer?
a.
b.
c.
d.
a maple tree
the blue-green bacteria known as cyanobacteria
Laurencia, a marine genus of Red Algae from Hawaii.
All of the above are producers.
3. In the food chain grass → grasshopper → snake → hawk, which organism(s) are the heterotrophs?
a.
b.
c.
d.
the grass
the grass and grasshopper
the hawk
the grasshopper, snake, and hawk
4. Which of the following statements is true about glucose and ATP? (1) Glucose is made during photosynthesis.
(2) The energy in sunlight is temporarily stored in glucose before it is transferred to ATP. (3) ATP is the
energy-carrying molecule that cells use for energy. (4) The processes that make ATP and glucose also recycle
oxygen in Earth’s atmosphere.
a.
b.
c.
d.
statement 1 only
statements 2 and 3 only
statements 1, 2, and 3 only
All 4 statements are correct.
5. Photosynthesis can be described as the process that
a.
b.
c.
d.
uses carbon dioxide and water, in the presence of sunlight, to produce food (glucose) and oxygen.
uses glucose and oxygen to produce energy for the cell (ATP), releasing carbon dioxide and water.
uses glucose and oxygen, in the presence of sunlight, to make ATP.
uses carbon dioxide and water, in the presence of sunlight, to produce ATP and oxygen.
6. Which statement best describes the relationship between a consumer and a producer?
a.
b.
c.
d.
A lion eating an antelope.
A caterpillar eating a leaf.
A snake eating a rat.
A flower absorbing sunlight.
7. Which of the following statements is true?
a.
b.
c.
d.
The products of photosynthesis are the reactants of cellular respiration.
The products of cellular respiration are the reactants of photosynthesis.
Both statements are true.
Neither statement is true.
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4.1. Energy for Life
8. Photosynthesis can be described as the process that
a.
b.
c.
d.
uses carbon dioxide and water, in the presence of sunlight, to produce food (glucose) and oxygen.
uses glucose and oxygen to produce energy for the cell (ATP), releasing carbon dioxide and water.
uses glucose and oxygen, in the presence of sunlight, to make ATP.
uses carbon dioxide and water, in the presence of sunlight, to produce ATP and oxygen.
9. Which statement best describes the relationship between a consumer and a producer?
a.
b.
c.
d.
A lion eating an antelope.
A caterpillar eating a leaf.
A snake eating a rat.
A flower absorbing sunlight.
10.Which of the following statements is true?
a.
b.
c.
d.
The products of photosynthesis are the reactants of cellular respiration.
The products of cellular respiration are the reactants of photosynthesis.
Both statements are true.
Neither statement is true.
11.The correct chemical formula for photosynthesis (in the presence of sunlight) is
a.
b.
c.
d.
6CO2 + 6O2 → C6 H12 O6 + 6H2 O.
6CO2 + 6H2 O → C6 H12 O6 + 6O2 .
C6 H12 O6 + 6O2 → 6CO2 + 6H2 O
C6 H12 O6 + 6CO2 → 6O2 + 6H2 O
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.1: Vocabulary I
Name
Class
Date
Match the vocabulary word with the proper definition.
Definitions
1. the process in which glucose is broken down and ATP is made
2. organism at the end of a food chain
3. shows how energy and matter flow from producers to consumers
4. also known as autotrophs
5. the ability to do work
6. stores chemical energy in a concentrated, stable form
7. the energy-carrying molecule that cells use for energy
8. process that stores energy from sunlight in the chemical bonds of glucose
9. organisms that make their own food
10. all animals and fungi and many single-celled organisms
11. organisms that must eat
12. organic molecules that store energy in their chemical bonds
Terms
a. ATP
b. autotroph
c. cellular respiration
d. consumer
e. decomposer
f. energy
g. food
h. food chain
i. glucose
j. heterotroph
k. photosynthesis
l. producer
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4.1. Energy for Life
Lesson 4.1: Vocabulary II
Name
Class
Date
Fill in the blank with the appropriate term.
1. Heterotrophs are living things that cannot make their own
2.
and
3. Glucose and
4.
are the two types of molecules organisms use for chemical energy.
are the products of photosynthesis.
, water, and energy are the products of cellular respiration.
5. Photosynthesis is the process in which energy from
6.
.
is transferred to glucose.
is the process in which energy from glucose is transferred to ATP.
7. Without photosynthesis, there would be no
in the atmosphere.
8. All organisms burn glucose to form
during cellular respiration.
9. The chemical formula of glucose is
.
10. Photosynthesis occurs in the
, and cellular respiration occurs in the
.
11.
make their own food, whereas
get food by eating other living things.
12. Living organisms get their
from food.
Lesson 4.1: Critical Writing
Name
Class
Date
Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences.
Draw a five level food chain, identifying autotrophs, heterotrophs, producers, and consumers.
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Name: ______________________________ Honors Biology Energy Storage Mechanisms Cell Energy Unit Overview: Cell Respiration (Plants and Animals) O2 CO2 C6H12O 6 Water Photosynthesis (Plants Only) Know the Terms: 1. NAD+ ________________________________________________________
2. NADH ________________________________________________________
3. H+ ___________________________________________________________
4. FAD _________________________________________________________
5. FADH2________________________________________________________
6. C6H12O6 _______________________________________________________
7. ADP __________________________________________________________
8. P ___________________________________________________________
9. ATP _________________________________________________________
10.NADPH ______________________________________________________
11.NADP+_______________________________________________________
17
Practice: For each statement identify where energy is stored and released. For each energy transfer identify it as involving an unstable bond, excited electrons, or a concentration gradient. 1. In glycolysis, nicotinamide adenine dinucleotide (NAD+) gains two electrons to become
nicotinamide adenine dinucleotide with hydrogen (NADH).
2. In the electron transport chain of cell respiration, energy from electrons is used to pump
protons against the concentration gradient into the inter-­‐membrane space.
3. Hydrogen ions diffuse down their concentration gradient through the inner membrane into the
matrix through a hydrogen ion channel termed ATP synthase. As the hydrogen ions return from
high concentration to low concentration ATP is formed from ADP and a phosphate.
4. In the Calvin Cycle of photosynthesis, ATP is used to add a phosphate group to phosphoglycerate
(3-­‐PGA) to make glyceraldehyde 3 phosphate (G3P).
5. In the Kreb Cycle of cell respiration a five carbon molecule is broken down into a four carbon
molecule and adds a phosphate group to ADP.
6. In photosystem one of the light reactions of photosynthesis, a nicotinamide adenine
dinucleotide phosphate (NADP+) is reduced to nicotinamide adenine dinucleotide phosphate
hydrogen (NADPH).
7. In the inner membrane of the mitochondria, hydrogen ions diffuse from a higher concentration
to a lower concentration and ATP synthase bonds phosphate to an adenosine diphosphate to
form ATP.
18
Energy Storage Method Storage Release Unstable Bonds Excited Electrons Concentration Gradient 19
Chloroplasts and Mitochondria
Plant cells and some Algae contain an organelle called the
chloroplast. The chloroplast allows plants to harvest energy from sunlight
to carry on a process known as Photosynthesis. Specialized pigments in the
chloroplast (including the common green pigment chlorophyll) absorb
sunlight and use this energy to combine carbon dioxide and water and make
GLUCOSE and OXYGEN. The complete the chemical reaction for
Photosynthesis is:
6 CO2 + 6 H2O + energy (from sunlight)
RAW MATERIALS
ENERGY
C6H12O6 + 6 O2
PRODUCTS
In this way, plant cells manufacture glucose and other carbohydrates
that they can store for later use. Photosynthetic cells found mainly in the
leaves may have thousands of chloroplasts.
QUESTIONS:
1. What type of cells contains chloroplasts?
2. What is the energy autotrophs use to make their own food?
3. The food making process is called ___________________.
4. What are the raw materials for photosynthesis?
5. What simple sugar is produced?
6. What gas is USED? ________________ RELEASED? ________
7. Where are most photosynthetic cells in plants found?
8. About how many chloroplasts can be found in photosynthetic cells?
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Chloroplasts are double membrane organelles with a smooth outer
membrane and an inner membrane folded into disc-shaped sacs called
thylakoids. Color and label the outer membrane light green. Thylakoids,
containing chlorophyll and other accessory pigments (red, orange, yellow,
brown), are in stacks called granum (grana, plural). Color and label the
grana (STACK) dark green in Figure 1. Grana are connected to each other
by structures called lamellae, and they are surrounded by a gel-like
material called stroma. Color and label the lamellae brown in figure 1.
Color and label the stroma light blue in Figure 1.
FIGURE 1-CHLOROPLAST
9. How many membranes surround a chloroplast?
10. The outer membrane is S____________.
11. The INDIVIDUAL SACS formed by the inner membrane are called
_________________ and are arranged in ___________ like
pancakes.
12. What pigment is found inside a thylakoid? What color will it be?
13. Other pigments that trap sunlight are called A_____________
pigments. What colors are these pigments?
21
14. STACKS of thylakoids are called G___________ (plural) or
GRANUM (singular).
15. Stacks or grana are connected to each other by _____________.
Light-capturing pigments in the grana are organized into photosystems.
On Figure 2, color and label a single thylakoid (SINGLE DISK) dark green.
In figure 2, color and label a granum (STACK) red.
FIGURE 2-THYLAKOID
Mitochondria are the powerhouses of the cell because they “burn” or
break the chemical bonds of glucose to release energy to do work in a
cell. Remember that this energy originally came from the sun and was
stored in chemical bonds by plants during photosynthesis. Glucose and
other carbohydrates made by plants during photosynthesis are broken
down by the process of aerobic cellular respiration (requires oxygen) in
the mitochondria of the cell. This releases energy (ATP) for the cell.
The more active a cell (such as a muscle cell), the more mitochondria it
will have. The mitochondria are bout the size of a bacterial cell and are
often peanut-shaped. Mitochondria have their own DNA and a double
membrane like the nucleus and chloroplast. The outer membrane is
smooth, while the inner membrane is convoluted into folds called cristae
in order to increase the surface area.
22
16. Why are mitochondria called the powerhouse of the cell?
17. What cell process occurs in the mitochondria?
18. Why do some cells have MORE mitochondria? Give an example.
19. What simple sugar is broken down in the mitochondria?
20. Where does the energy in glucose come from ORIGINALLY?
21. Where is this energy stored in glucose?
22. Why is cellular respiration an aerobic process?
23. What energy is released when the chemical bonds of glucose are
broken?
24. Name two other organelles besides the mitochondria that contain
DNA and have a double membrane.
25. Describe the outer membrane of the mitochondria.
26. Why is the inner mitochondrial membrane folded?
27. What are the folds called?
23
Color and label the outer membrane pink and the cristae red on
figure 3. This greatly increases the surface area of the membrane so
that carbohydrates (simple sugars) can combine with oxygen to produce
ATP, adenosine triphosphate (the energy molecule of the cell). The
electron transport chain takes place across the membranes of the
cristae (crista, singular). Inside the folds or cristae is a space called
the matrix that contains enzymes needed for the Kreb's Cycle? Color
and label the matrix yellow on figure 3.
FIGURE 3 - MITOCHONDRIA
Mitochondria
Adenosine triphosphate (ATP) is the energy molecule used by all cells
to do work. It is a nucleotide consisting of a nitrogen-containing base
(adenine, thymine, cytosine, or guanine), a 5-carbon sugar, and 3 phosphate
groups. ATP is able to store and transport chemical energy within cells.
The LAST TWO phosphate groups (PO4), are joined by HIGH-ENERGY
bonds. When these bonds are broken, energy is released for cells to use
and ADP forms. Enzymes help to break and reform these high-energy
bonds.
28. What does ATP stand for?
29. What three main things make up an ATP molecule?
30. How many high-energy bonds does ATP contain?
24
31. Where are these high-energy bonds found in ATP?
32. What helps weaken these bonds so energy can be released and then
later help reform them?
33. When ATP loses a phosphate group __________ is released for cells
and a molecule of _________ forms.
In Figure 4, COLOR the 5-carbon sugar RED and LABEL it RIBOSE.
COLOR and LABEL the nitrogen-base DARK BLUE. COLOR and LABEL
the 3 phosphate groups YELLOW, and COLOR & LABEL the 2 highenergy bonds GREEN.
FIGURE 4 – ATP MOLECULE
Questions:
34. What is the energy molecule of the cell called?
35. What macromolecule made by plants is "burned" in the mitochondria?
36. Where is chlorophyll found in the chloroplast?
37. In which part of a plant would you expect to find the most chloroplasts and why?
38. How would the number of mitochondria in an insect's wing compare to the amount
found in other cells in an insect's body? Explain your answer.
25
Name___________________________________________________ Date_____________ Period_______
Photosynthesis: Making Energy
Objective:__________________________________________________________________________________
__________________________________________________________________________________________
Chloroplasts
Photosynthesis is a process in which sunlight energy is used to make
glucose. The site of photosynthesis is in the chloroplast – an organelle
found in the leaves of green plants. The main functions of chloroplasts are
to produce food (glucose) during photosynthesis, and to store food
energy. Chloroplasts contain the pigment, chlorophyll. Chlorophyll absorbs
most of the colors in the color spectrum, and reflects only green and
yellow wavelengths of light. This is why we see leaves as green or yellow –
because these colors are reflected into our eyes.
1. What is photosynthesis? ______________________________________________________
_________________________________________________________________________
2. Where does photosynthesis occur? ______________________________________________
3. What are chloroplasts and where are they found? ___________________________________
_________________________________________________________________________
4. What are the two main functions of chloroplasts? ___________________________________
5. Why doe most leaves appear green? _____________________________________________
6. What is the primary pigment found in the chloroplast? ________________________________
Photosynthesis
Glucose is another name for sugar. The molecular formula for glucose is C6H12O6. Plants make sugar by
using the energy from sunlight to transform CO2 from the air with water from the ground into glucose.
This process, called photosynthesis occurs in the chloroplast of the plant cell. During this process,
oxygen (O2) is created as a waste product and is released into the air for us to breath. The formula for
photosynthesis is:
(reactants)
(products)
CO2 + H2O + sunlight ----> C6H12O6 + O2
This formula says that carbon dioxide + water molecules are combined with the energy from sunlight to
produce sugar and oxygen. The reactants in photosynthesis (what is used) are CO2, water and sun. The
plant gets water from the ground through its roots. The plant collects carbon dioxide from the air. Much
of the carbon dioxide comes from living organisms that exhale (breath it out) it, but some also comes
from factory smokestacks and car fumes.
7. What is the formula for photosynthesis? __________________________________________
26
Name___________________________________________________ Date_____________ Period_______
8. What three things are used to make glucose in photosynthesis? _________________________
_________________________________________________________________________
9. Where does the water come from? ______________________________________________
10. Where does the water enter the plant? ___________________________________________
11. Name 3 some sources of CO2. _________________________________________________
12. What type of energy does the plant use to convert CO2 and H2O into sugar? ________________
The products are glucose and oxygen. The glucose produced is used by the plant for energy and growth.
We also use this glucose by eating plants. The oxygen produced is released into the air for us to breath.
Photosynthesis is essential for all life on earth, because it provides food and oxygen. Plants are
considered autotrophs because unlike us humans, they can make their own food using this process.
13. What is produced in photosynthesis? _____________________________________________
14. What is the glucose used for? __________________________________________________
15. What is the oxygen used for? __________________________________________________
16. Here are three different ways to visualize the photosynthesis reaction: Is it easier for
you to understand the reaction by using pictures, words, or symbols (see above)? Why?
_____________________________________________________________________
_____________________________________________________________________
Photosynthesis in pictures
Photosynthesis in words
Carbon dioxide and
water combine with
sunlight to create
oxygen and glucose.
Photosynthesis in symbols
light
CO + H2O → C6H12O6 + O2
Essential Question: Describe, using scientific terms, how plants turn sunlight into energy? Make
sure to refer to the chemical equation to photosynthesis and discus the reactants and products.
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
___________________________________________________________________________
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Name___________________________________________________ Date_____________ Period_______
Cellular Respiration: Breaking down Energy
Objective:__________________________________________________________________________________
__________________________________________________________________________________________
Mitochondria are known as the powerhouses of the cell. They are organelles that act like a digestive system that takes
in nutrients, breaks them down, and creates energy for the cell. The process of creating cell energy is known as cellular
respiration. Most of the chemical reactions involved in cellular respiration happen in the mitochondria. A mitochondrion
is shaped perfectly to maximize its efforts.
1. What process happens in the mitochondria?
2. What is the purpose of the process in #1 (what does it create)?
Introduction to Cellular Respiration
Organisms, such as plants and algae, can trap the energy in sunlight through photosynthesis and store it in the
chemical bonds of carbohydrate molecules. The principal carbohydrate formed through photosynthesis is
glucose. Other types of organisms, such as animals, fungi, protozoa, and a large portion of the bacteria, are
unable to perform this process. Therefore, these organisms must rely on the carbohydrates formed in plants to
obtain the energy necessary for their metabolic processes. This means they must eat plants and other animals in
order to gain energy.
4. Some organisms perform photosynthesis to produce energy. Other organisms cannot do photosynthesis. What can
they do in order to generate energy?______________________________________________________
______________________________________________________________________________
5. Animals and other organisms obtain the energy available in carbohydrates through the process of cellular
respiration. What is the purpose of cellular respiration? _________________________________________
______________________________________________________________________________
______________________________________________________________________________
Cells take the carbohydrates into their cytoplasm, and through a complex series of metabolic processes, they
break down the carbohydrates and release the energy. The energy is generally not needed immediately; rather
it is used to combine adenosine diphosphate (ADP) with another phosphate to form adenosine triphosphate
(ATP) molecules. The ATP can then be used for processes in the cells that require energy, much as a battery
powers a mechanical device. During the process of cellular respiration, carbon dioxide is given off. Plant cells can
use this carbon dioxide during photosynthesis to form new carbohydrates.
6. What happens to carbohydrates during cellular respiration? _____________________________________
______________________________________________________________________________
______________________________________________________________________________
7. What is the chemical energy in the cell called? _________
8. What does ATP stand for? ________________________________________________________
9. What is one product of cellular respiration? ________________
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Name___________________________________________________ Date_____________ Period_______
10. How do animals get rid of the carbon dioxide? ______________________________ What body system is involved
with removing this waste? __________________________
Also in the process of cellular respiration, oxygen gas is required to serve as an acceptor of electrons. This oxygen is
identical to the oxygen gas given off during photosynthesis.
11. (Circle one) Oxygen is a
released?)
PRODUCT
OR
REACTANT
of respiration? (In other words, is it needed or
Energyproducing
process
Reaction
Location in cell
Photosynthesis
12.
______________________________________________
Chloroplast
Cellular
respiration
13.
__________________________
Reflection Question: Explain the relationship between photosynthesis and cellular respiration. Be sure to
include the main purpose of both and where they occur inside the cell.
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
HUMANS AND PLANTS
Humans need plants. All animals do. Humanity's relationship with plants has actually made it possible for us to
have a civilization. Before we had cities, humans went around in little packs and were hunter-gatherers. We ate
rats, birds, berries, and whatever food we could find. It wasn't very efficient. One day
someone had the bright idea to plant the plants we like to eat. When humans did that, they
were able to stay in one place full time. Then came the cities and a huge system of agriculture
to support millions of people.
BIG TIME FARMING
As time has passed, we have taken farming to new levels. We have manipulated species to
create big apples and large ears of corn. The plants would never have done it in the wild. It took man to change
the plants. We are also moving toward the genetic alteration of plants. We're trying to make plants that are
resistant to disease and bugs. These stronger plants will allow our crops to give us more food from the same
amount of space.
1. Genetic alteration probably refers to altering what…. _____________________________ (found in the
nucleus)
29
Adenosine TriPhosphate Name: _____________________
Web Exploration
Period: __________
ATP
Go to http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect04.htm
Click on the “ATP - Adenosine triphosphate - a close relative to Adenine, a nucleotide found in
DNA” link.
1.) Draw the molecule of ATP. Show all bonds.
2.) What type of sugar is in the molecule? __________________________________________________
3.) What nitrogenous base is found in an ATP molecule? _____________________________________
4.) How is it similar to a nucleotide? _______________________________________________________
_______________________________________________________________
5.) How is it different? ___________________________________________________________________
_______________________________________________________________
Go back to the website to answer the following questions.
6.) What happens when the last phosphate group is broken off from the ATP molecule? __________
_______________________________________________________________
7.) What molecules are formed? __________________________________________________________
8.) What is released when the bond is broken? ______________________________________________
9.) One muscle cell can consume and regenerate over _______________________________________
10.) If ATP couldn't be regenerated ________________________________________________________
_______________________________________________________________
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ATP C YCLE Go to http://www.youtube.com/watch?v=Lx9GklK0xQg
11.) What is the ATP cycle? _______________________________________________________________
_______________________________________________________________
12.) What is phosphorylation? _____________________________________________________________
_______________________________________________________________
13.) Compare and contrast endergonic and exergonic reactions in the ATP cycle. _________________
_______________________________________________________________
_______________________________________________________________
14.) On the diagram, please label the following items: ATP, ADP, inorganic phosphate, energy input,
energy released.
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
4.2 Photosynthesis: Sugar as Food
Lesson 4.2: True or False
Name
Class
Date
Write true if the statement is true or false if the statement is false.
1. Photosynthesis provides almost all of the energy used by living things on Earth.
2. Earth’s oxygen comes from photosynthesis.
3. In photosynthesis, the Calvin cycle comes before the light reactions.
4. ATP and NADPH are the reactants of the light reactions.
5. Electron transport occurs in the thylakoid membranes.
6. All cells have chloroplasts.
7. During the Calvin cycle, NADPH and ATP are used to make glucose.
8. Photons of sunlight can excite and energize electrons.
9. A chemiosmotic gradient causes hydrogen ions to flow across the thylakoid membrane into the stroma.
10. Like photosynthesis, chemosynthesis also relies on sunlight.
11. Two turns of the Calvin cycle produce two molecules of glucose.
12. The Calvin cycle takes place in the stroma surrounding the thylakoid membranes of the chloroplast.
13. During the light reactions, water molecules are made.
14. Light is absorbed by photosystems in the thylakoid membranes of chloroplasts.
15. Both stages of photosynthesis need sunlight to proceed.
Lesson 4.2: Critical Reading
Name
Class
Date
Read these passages from the text and answer the questions that follow.
Photosynthesis Stage I: The Light Reactions
The first stage of photosynthesis is called the light reactions. During this stage, light is absorbed and transformed to
chemical energy in the bonds of NADPH and ATP. You can read about this process below.
Steps of the Light Reactions
The light reactions occur in several steps, all of which take place in the thylakoid membrane.
• Step 1: Units of sunlight, called photons, strike a molecule of chlorophyll in photosystem II of the thylakoid
membrane. The light energy is absorbed by two electrons (2 e− ) in the chlorophyll molecule, giving them
enough energy to leave the molecule.
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4.2. Photosynthesis: Sugar as Food
• Step 2: At the same time, enzymes in the thylakoid membrane use light energy to split apart a water molecule.
This produces:
– two electrons (2 e− ). These electrons replace the two electrons that were lost from the chlorophyll
molecule in Step 1.
– an atom of oxygen (O). This atom combines with another oxygen atom to produce a molecule of oxygen
gas (O2 ), which is released as a waste product.
– two hydrogen ions (2 H+ ). The hydrogen ions, which are positively charged, are released inside the
membrane in the thylakoid interior space.
• Step 3: The two excited electrons from Step 1 contain a great deal of energy, so, like hot potatoes, they need
something to carry them. They are carried by a series of electron-transport molecules, which make up an
electron transport chain. The two electrons are passed from molecule to molecule down the chain. As this
happens, their energy is captured and used to pump more hydrogen ions into the thylakoid interior space.
• Step 4: When the two electrons reach photosystem I, they are no longer excited. Their energy has been
captured and used, and they need more energy. They get energy from light, which is absorbed by chlorophyll
in photosystem I. Then, the two re-energized electrons pass down another electron transport chain.
• Step 5: Enzymes in the thylakoid membrane transfer the newly re-energized electrons to a compound called
NADP+ . Along with a hydrogen ion, this produces the energy-carrying molecule NADPH. This molecule is
needed to make glucose in the Calvin cycle.
• Step 6: By now, there is a greater concentration of hydrogen ions —and positive charge —in the thylakoid
interior space. This difference in concentration and charge creates what is called a chemiosmotic gradient. It
causes hydrogen ions to flow back across the thylakoid membrane to the stroma, where their concentration
is lower. Like water flowing through a hole in a dam, the hydrogen ions have energy as they flow down
the chemiosmotic gradient. The enzyme ATP synthase acts as a channel protein and helps the ions cross
the membrane. ATP synthase also uses their energy to add a phosphate group (Pi) to a molecule of ADP,
producing a molecule of ATP. The energy in ATP is needed for the Calvin cycle.
Questions
1. In one sentence, describe what happens during the light reactions.
2. In which step(s) of the light reactions is sunlight absorbed?
3. Why is water “split” during the light reactions?
4. What is an electron transport chain? What is its role during these light reactions?
5. How is ATP made during the light reactions?
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.2: Multiple Choice
Name
________
Class
Date
Circle the letter of the correct choice.
1. Most autotrophs make “food” through the process of
a.
b.
c.
d.
cellular respiration.
chemosynthesis.
homeostasis.
photosynthesis.
2. The correct sequence of events in the light reactions is
a.
b.
c.
d.
absorption of sunlight, electrons flow down the electron transport chain, ATP is made, NADPH is made.
absorption of sunlight, splitting of water, electrons flow down the electron transport chain, ATP is made.
electrons flow down the electron transport chain, NADPH is made, ATP is made, water is split.
absorption of sunlight, electrons flow down the electron transport chain, NADPH is made, water is split.
3. The Calvin cycle occurs
a.
b.
c.
d.
in the granum of the thylakoid membranes of the chloroplast.
in the stroma surrounding the inner membrane of the chloroplast.
in the stroma surrounding the thylakoid membranes of the chloroplast.
in the granum inside the inner membrane of the chloroplast.
4. By the end of the light reactions, energy from sunlight
a.
b.
c.
d.
has been stored in chemical bonds of NADPH and ATP.
has been transferred to glucose.
has entered the Calvin cycle.
is ready for use in the cell.
5. ATP synthase is
a. both an enzyme that makes ATP and a channel protein, and helps hydrogen ions cross the thylakoid
membrane.
b. both an enzyme that makes ATP and a channel protein, and helps hydrogen ions cross the chloroplast
inner membrane.
c. both an enzyme that makes ATP and a carrier protein, and helps hydrogen ions cross the thylakoid
membrane.
d. both an enzyme that makes ATP and a carrier protein, and helps hydrogen ions cross the chloroplast
inner membrane.
6. Essentially, the oxygen we breathe is
a.
b.
c.
d.
necessary for the light reactions to proceed.
a waste product of photosynthesis.
a reactant of the Calvin cycle.
essential for the homeostasis of the plant cell.
7. The Calvin cycle
a.
b.
c.
d.
starts with the molecule RuBP.
uses the energy in ATP and NADPH from the light reactions.
turns twice to produce one molecule of glucose.
all of the above
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4.2. Photosynthesis: Sugar as Food
8. The Calvin cycle occurs
a.
b.
c.
d.
in the granum of the thylakoid membranes of the chloroplast.
in the stroma surrounding the inner membrane of the chloroplast.
in the stroma surrounding the thylakoid membranes of the chloroplast.
in the granum inside the inner membrane of the chloroplast.
9. By the end of the light reactions, energy from sunlight
a.
b.
c.
d.
has been stored in chemical bonds of NADPH and ATP.
has been transferred to glucose.
has entered the Calvin cycle.
is ready for use in the cell.
10.ATP synthase is
a. both an enzyme that makes ATP and a channel protein, and helps hydrogen ions cross the thylakoid
membrane.
b. both an enzyme that makes ATP and a channel protein, and helps hydrogen ions cross the chloroplast
inner membrane.
c. both an enzyme that makes ATP and a carrier protein, and helps hydrogen ions cross the thylakoid
membrane.
d. both an enzyme that makes ATP and a carrier protein, and helps hydrogen ions cross the chloroplast
inner membrane.
11.Essentially, the oxygen we breathe is
a.
b.
c.
d.
necessary for the light reactions to proceed.
a waste product of photosynthesis.
a reactant of the Calvin cycle.
essential for the homeostasis of the plant cell.
12.The Calvin cycle
a.
b.
c.
d.
starts with the molecule RuBP.
uses the energy in ATP and NADPH from the light reactions.
turns twice to produce one molecule of glucose.
all of the above
13.How do bacteria that live deep below the ocean’s surface make food?
a.
b.
c.
d.
by photosynthesis
by chemosynthesis
by cellular respiration
They eat other organisms.
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.2: Vocabulary I
Name
Class
Date
Match the vocabulary word with the proper definition.
Definitions
1. a green pigment
2. main product of photosynthesis
3. process in which chemical energy, instead of sunlight, is used to make “food”
4. process in which sunlight is used to make “food”
5. sac-like membranes that make up the grana within the chloroplast
6. organelle of photosynthesis
7. space outside the thylakoid membranes within the chloroplast
8. energy carrying molecule
9. series of electron-transport molecules, which pass electrons from molecule to molecule
10. groups of molecules where sunlight is absorbed during the light reactions
11. stage of photosynthesis in which the energy from sunlight is stored in ATP and NADPH
12. stage of photosynthesis in which glucose is made
Terms
a. Calvin cycle
b. chemosynthesis
c. chlorophyll
d. chloroplast
e. electron transport chain
f. glucose
g. light reactions
h. NADPH
i. photosynthesis
j. photosystem
k. stroma
l. thylakoid membrane
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4.2. Photosynthesis: Sugar as Food
Lesson 4.2: Vocabulary II
Name
Class
Date
Fill in the blank with the appropriate term.
1.
are the organelles where photosynthesis takes place.
2. Stage I of photosynthesis is called the
.
3. Stage II of photosynthesis is called the
.
4. During the first stage of photosynthesis, a molecule of
gas is released.
5. Making food with chemical energy instead of sunlight is called
6. Chloroplasts contain
membranes.
7. Most
.
, which are made out of sac-like membranes, known as
make food using photosynthesis.
8. The green pigment,
, absorbs light to start photosynthesis.
9. During the first stage of photosynthesis, two ________________ are passed from molecule to
molecule down the electron-transport chain.
10.
turns of the Calvin cycle produce one molecule of
.
11. During the light reactions,
and are produced.
12. During the Calvin cycle,
is produced.
Lesson 4.2: Critical Writing
Name
Class
Date
Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences.
What are the two stages of photosynthesis? Discuss these two stages and how they are related.
37
-
Name: Date: Period: Photosynthesis: An Overview
Parts of a Leaf and Types of Photosynthesis
Directions: Watch the parts of a leaf video and answer the following questions. 1. Why do leaves have a large surface area? 2. What are stomata? What are guard cells? 3. Stomata open to let ___________________________ into leaves. Stomata cannot stay open for an extended period of time because too much __________________________ will transpire. 4. What is the purpose of the waxy cuticle? Directions: Use online resources to research the three different types of photosynthesis. Summarize the types of photosynthesis in the following table. Summary of C3, C4, and CAM Photosynthesis C3 C4 CAM 38
Directions: Research each of the provided plant species. Do you think these plants use C3, C4, or CAM photosynthesis? Fully explain your reasoning. Plant Species Type of Photosynthesis Explanation Wheat Corn Sugar Cane Aloe Tomato Evergreen Trees 39
Photosynthesis Overview Name: _____________________________
Web Analysis Activity
Period: _____________
Photosynthesis is the process by which plants, some bacteria,
and some protists use the energy from sunlight to produce
sugar, which cellular respiration converts into ATP, the "fuel"
used by all living things. The conversion of unusable sunlight
energy into usable chemical energy is associated with the
actions of the green pigment chlorophyll. Most of the time, the
photosynthetic process uses water and releases the oxygen
that we absolutely must have to stay alive. Oh yes, we need
the food as well!
Objectives:
! Identify the molecules involved in photosynthesis
! Analyze the movement of the molecules involved in photosynthesis
! Create links and pathways of essential molecules between plants and animals
Here’s how to do it!
" Type in the following link: http://www.pbs.org/wgbh/nova/methuselah/photosynthesis.html#
" Read the introduction entitled “Illuminating Photosynthesis” by Rick Groleau and answer
the following questions.
1. What process is responsible for feeding all life on earth? ________________
2. Energy from the sun gets converted into what during photosynthesis? ______
3. What gas is generated by plants and used by animals? __________________
4. How do animals contribute to photosynthesis? ________________________
____________________________________________________________
Next, click on “PRINTABLE VERSION.” This feature takes a look at the oxygen/carbon
dioxide cycle and at the process of photosynthesis. Also included are a few puzzlers
with answers that may surprise you.
" Read the introductory poem and answer the question below.
40
1.) This feature shows how plants create ____________ and the
____________ of ____________.
" Click on “The Cycle”.
2.) Click on each of the following items, and explain what happens with the molecules CO2
(carbon dioxide), H2O (water) and O2 (oxygen gas)—BE SPECIFIC and say WHERE
THEY ARE GOING:
A.) The container of water: _________________________________________
____________________________________________________________
B.) The girl: _____________________________________________________
____________________________________________________________
C.) Sketch the diagram of the girl, water, plant, and window. Draw the flow of the
molecules and light.
3.) What gas does the child provide for the plant to use? ________________________
4.) What gas does the plant provide for the child to use? ________________________
5.) According to this animation, what 3 main things does the plant need for photosynthesis
to occur?
A.) ___________________________________________________________
B.) ___________________________________________________________
C.) ___________________________________________________________
41
" Click on “The Atomic Shuffle”.
6.) What type of molecule is shown in the leaf? _____________________________
7.) Draw one of the molecules, as it is shown in the leaf.
8.) According to the reading, these molecules “do not come from the tap.” What two
places do they come from?
A.) ___________________________________________________________
B.) ___________________________________________________________
9.) What is “stripped” from each water molecule_____________________________
10.) From where does the cell get the energy to do this? _______________________
11.) The stripped molecules form pairs. Where does it go after this? _____________
______________________________________________________________
12.) What gas enters the leaf? __________________________________________
13.) This gas enters through “holes” in the leaf. What are they called? ____________
14.) What molecule is formed once again? __________________________________
15.) Another
molecule is
formed (“and
boy is it
sweet”). Draw
this molecule as
shown.
16.) What is the name of this molecule? ___________________________________
42
17.) Write the simplified equation for photosynthesis in the box below.
" Click on “Three Puzzlers”. Answer each of the following questions, and explain in your
own words.
18.) Can a tree produce enough oxygen to keep a person alive? Explain.
______________________________________________
______________________________________________
______________________________________________
19.) Can a plant stay alive without light?
______________________________________________
______________________________________________
______________________________________________
20.) Can a plant survive without oxygen? Explain.
______________________________________________
______________________________________________
______________________________________________
43
Name: __________________________
Period: ________
Date: __________________
Photosynthesis Case Study
The Scenario:
Heidi has become interested in gardening. She has planted a small potted garden
in her dorm room, but she is distressed because her garden will not grow. She
waters the plants every few days, just like the gardening books say. She has
placed them near the window to get light; but her roommate, Mary, insists on
keeping a translucent green curtain in the window. Mary wants to keep the
curtain closed because she likes to sleep late, and she often forgets to open it
when leaving for class. Heidi hasn’t made a big deal about it because it is
translucent and lets some light through.
One morning, Heidi asks Mary to stop at Pike’s Nursery to buy some fertilizer on
her way home from work. Mary replies that she can save Heidi some money by
getting some fertilizer from her dad’s storage shed when she goes home the next
weekend. Mary’s dad is a corn farmer and has all the best plant products. When
Mary returns from home, she brings Heidi a bit of fertilizer in a paper bag labeled
Aatrex (Atrazine).
After fertilizing the plants once, Heidi notices the plants seem to be dying; the
leaves are turning yellow around the edges. Finally, Heidi asks Mary to drive her
to Pike’s so that she can ask someone who works there about why her plants are
dying. When she arrives at Pike’s, Heidi begins talking to an employee named
John. She tells him everything. When she finishes, John tries to hold back the
laughter as he explains to Heidi why her plants are dying.
Your Task:
Part I:
1. Identify two gardening mistakes that Heidi made:
2. Given what you are learning about photosynthesis, why were the plants not
growing? Fully explain.
3. Why are the plants now dying? Include details.
44
4. What does Heidi need to do to fix the problem?
Part II:
In 2 paragraphs (5 sentences each), explain what John told Heidi. Use your
answers to the questions above to guide you.
45
Name _______________________________
Period _____
Date ____________________
WORKSHEET ON PHOTOSYNTHESIS
1. What is the first step of photosynthesis?
2. Where does it occur in the cell?
3. What are the reactants?
4. What are the products?
5. What is the second step of photosynthesis?
6. Where does it occur in the cell?
7. What are the reactants?
8. What are the products?
9. What is the electron carrier in photosynthesis?
10. The main point of photosynthesis is to make:
11. What is the summary equation for photosynthesis?
12. the ultimate source of energy for photosynthesis is the ________.
13. What is a photosystem?
14. Where are they located?
15. What is the main pigment found in them?
16. What is a photon?
17. Define a pigment:
18. What happens to chlorophyll when a photon of light hits it?
19. You can see colors of light that are _________, but can’t see colors that are __________.
20. The dark reactions require the input of carbon dioxide, ATP and NADPH to produce:
21. True or false. Photosynthesis is:
a. Found in all living things
b. Found in green plants
c. Produces oxygen
d. Produces carbon dioxide
e. Uses oxygen
f. Uses carbon dioxide
g. Makes glucose
h. Uses glucose
i. Uses oxidation reduction reactions
The light reactions of photosynthesis requires __________ of light, and the splitting of water, to
produce ATP, NADPH and ___________ as products.
46
Name: Date: Period: Cellular Respiration Review Questions 1. Explain why the cells in all biological organisms need to carry out the reaction,
ATP à ADP + phosphate. How is this reaction useful? 2. Where does the glucose in our bodies come from?
3. Write the equation for cellular respiration and label each reactant/product as
glycolysis, Krebs Cycle, or electron transport chain. ___________________ + ________________ à _____________________ + ___________________+ _________________ 4. Is the following sentence accurate? Explain why or why not.
Cellular respiration makes the energy needed for biological processes. 5. Annotate the following diagram with information from your notes.
47
Scientific Explanation Connections Between Cellular Respiration and Photosynthesis Task: You are going to create a detailed, scientific paragraph that explains your thoughts and opinions about the following scenario. Scenario: A terrible virus has reached Western Pennsylvania. This virus drastically affects the process of cellular respiration by attacking the ability of the electron transport chain to make ATP. Recall at the electron transport chain provides a large amount of energy, 32 ATP molecules! Without the electron transport chain, the process of cellular respiration is essentially nonexistent. What would happen to the biosphere if cellular respiration did not exist? Requirements: You must correct use at least five of the terms from the following list. The manner in which you use the words must show that you understand their meaning. For example, the statement, ‘In my opinion, cellular respiration is an important process,’ would not count as an appropriate use of the word. Make sure to underline, highlight, or bold your five required terms. List of Terms Autotrophs Electron Carriers Energy Krebs Cycle ADP Heterotrophs ATP Sunlight Electron Transport Calvin Cycle 48
Photosynthesis Oxygen Mitochondria Glycolysis Sugar Cellular Respiration Carbon Dioxide Chloroplast Light-­‐Dependent Water Name: _____________________________________
TOPIC 5: Cellular Energy
Please use the Council Rock Video Podcast to guide you
1. What are examples of autotrophs?
2. What are examples of heterotrophs?
3. The most instant form of energy is known as ____________.
4. Why is ATP a high energy molecule?
5. Complete the photosynthesis equation below
__CO2 + ___ H2O + _________/enzymes  C6H12O6 +___6O2
6. If the photosynthesis equation is reversed, then it is the formula for _____________________________.
7. The _________ dependent reactions and the light _____________________ reactions make up
photosynthesis.
8. Place a “D” if the statement refers to the light dependent reactions and an “I” if it refers to the light
independent reactions
____ water is split into oxygen, protons, and electrons
____CO2 is taken in and converted into carbohydrates
____ light energy is not needed
____ light energy is needed
9. What initial process splits a molecule of glucose into 2 3-carbon molecules? ________________________
10. What is the NET ATP yield from glycolysis? _______
11. What are the two different types of fermentation mentioned?
a.
b.
12. (Circle one) CO2 is created during electron transport chain / Kreb’s cycle
13. In the electron transport chain, oxygen joins with electrons and protons to make ___________.
14. By going through glycolysis, Kreb’s Cycle, and Electron transport chain, a cell can make between _____ and
______ ATP as opposed to just the 2 of glycolysis.
Biology Keystone Review—2012-2013
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
4.3 Powering the Cell: Cellular Respiration
Lesson 4.3: True or False
Name
Class
Date
Write true if the statement is true or false if the statement is false.
1. Like photosynthesis, cellular respiration begins with an electron transport chain.
2. Cellular respiration that proceeds in the presence of oxygen is called aerobic respiration.
3. Oxygen is the final electron acceptor during anaerobic respiration.
4. Cellular respiration occurs in the mitochondria.
5. Mitochondria posses their own DNA and ribosomes.
6. Just like the chloroplast, the stroma separates the inner and outer membranes of the mitochondria.
7. The Krebs cycle comes after glycolysis, during cellular respiration.
8. Cellular respiration begins with the absorption of sunlight by the mitochondria photosystems.
9. ATP synthase pumps, by active transport, hydrogen ions back into the mitochondria matrix.
10. The first reaction of the Krebs cycle produces citric acid.
11. One molecule of glucose holds enough energy to produce up to 38 ATP.
12. The Krebs cycle produces four ATP.
13. Whereas plants perform photosynthesis, plants and animals perform cellular respiration.
14. Aerobic respiration evolved prior to anaerobic respiration.
15. Two NADPH are made during glycolysis.
Lesson 4.3: Critical Reading
Name
Class
Date
Read these passages from the text and answer the questions that follow.
Cellular Respiration Stage III: Electron Transport
Electron transport is the final stage of aerobic respiration. In this stage, energy from NADH and FADH2 , which
result from the Krebs cycle, is transferred to ATP. Can you predict how this happens? (Hint: How does electron
transport occur in photosynthesis?)
Transporting Electrons
1. High-energy electrons are released from NADH and FADH2 , and they move along electron transport chains, like
those used in photosynthesis. The electron transport chains are on the inner membrane of the mitochondrion. As
the high-energy electrons are transported along the chains, some of their energy is captured. This energy is used to
pump hydrogen ions (from NADH and FADH2 ) across the inner membrane, from the matrix into the intermembrane
space.
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4.3. Powering the Cell: Cellular Respiration
Making ATP
The pumping of hydrogen ions across the inner membrane creates a greater concentration of the ions in the intermembrane space than in the matrix. This chemiosmotic gradient causes the ions to flow back across the membrane
into the matrix, where their concentration is lower. ATP synthase acts as a channel protein, helping the hydrogen
ions cross the membrane. It also acts as an enzyme, forming ATP from ADP and inorganic phosphate. After passing
through the electron-transport chain, the “spent” electrons combine with oxygen to form water. This is why oxygen
is needed; in the absence of oxygen, this process cannot occur.
How Much ATP?
You have seen how the three stages of aerobic respiration use the energy in glucose to make ATP. How much ATP is
produced in all three stages? Glycolysis produces 2 ATP molecules, and the Krebs cycle produces 2 more. Electron
transport begins with several molecules of NADH and FADH2 from the Krebs cycle and transfers their energy into as
many as 34 more ATP molecules. All told, then, up to 38 molecules of ATP can be produced from just one molecule
of glucose in the process of aerobic respiration.
Questions
1. In photosynthesis, electron transport comes at the beginning of the process. Where does electron transport occur
during cellular respiration?
2. What is the role of the electron transport chain in cellular respiration?
3. Why is the role of oxygen in cellular respiration?
4. Describe ATP synthase and its role.
5. Summarize how up to 38 molecules of ATP are produced for each glucose molecule.
Lesson 4.3: Multiple Choice
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Name
Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Class
Date
Circle the letter of the correct choice.
1. Glycolysis
a.
b.
c.
d.
uses 2 ATPs and makes 2 ATPs, 2 NADHs, and 2 pyruvates.
uses 2 ATPs and makes 4 ATPs, 2 NADHs, and 2 pyruvates.
uses 4 ATPs and makes 2 ATPs, 2 NADHs, and 2 pyruvates.
uses 2 ATPs and makes 4 ATPs, 4 NADHs, and 2 pyruvates.
2. Cellular respiration in the presence of oxygen is called
a.
b.
c.
d.
anaerobic respiration.
glycolysis.
aerobic respiration.
oxygen respiration.
3. The correct order of stages of cellular respiration is
a.
b.
c.
d.
glycolysis - the Calvin cycle - electron transport.
the light reactions - glycolysis - the Krebs cycle.
glycolysis - the Krebs cycle - electron transport.
electron transport - glycolysis - the Krebs cycle.
4. Where are the electron transport chains of cellular respiration located?
a.
b.
c.
d.
in the inner membrane of the mitochondrion
in the matrix of the mitochondrion
in the intermembrane space of the mitochondrion
in the outer membrane of the mitochondrion
5. The final electron acceptor at the end of cellular respiration is
a.
b.
c.
d.
hydrogen.
oxygen.
water.
ATP synthase.
6. The chemical formula of cellular respiration is
a.
b.
c.
d.
6CO2 + 6H2 O → C6 H12 O6 + 6O2 .
C6 H12 O6 + O2 → CO2 + H2 O.
CO2 + H2 O → C6 H12 O6 + O2 .
C6 H12 O6 + 6O2 → 6CO2 + 6H2 O.
7. The chemiosmotic gradient of cellular respiration is an
a. ion gradient made by the pumping of hydrogen ions across the inner membrane using the energy
electrons as they are transported down the electron transport chain.
b. ion gradient made by the pumping of hydrogen ions across the outer membrane using the energy
electrons as they are transported down the electron transport chain.
c. ion gradient made by the pumping of oxygen ions across the inner membrane using the energy
electrons as they are transported down the electron transport chain.
d. ion gradient made by the diffusion of hydrogen ions across the inner membrane using the energy
electrons as they are transported down the electron transport chain.
8. In the presence of oxygen, one glucose molecule has the energy to make up to
a. 4 FADH2 . b. 12 NADH.
c. 38 ATP.
Lesson 4.3: Vocabulary I
52
d. all of the above
of
of
of
of
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4.3. Powering the Cell: Cellular Respiration
Name
Class
Date
Match the vocabulary word with the proper definition.
Definitions
1. channel protein and enzyme that makes ATP
2. also known as the Krebs cycle
3. energy-carrying compound produced during the Krebs cycle
4. end product of glycolysis
5. cellular respiration in the absence of oxygen
6. energy-carrying compound involved in stage I and stage II of cellular respiration
7. a greater concentration of hydrogen ions in the intermembrane space than in the mitochondrial matrix
8. stage II of cellular respiration
9. “folds” created by the mitochondria inner membrane
10. glucose splitting
11. involved in stage III of cellular respiration
12. cellular respiration in the presence of oxygen
Terms
a. aerobic respiration
b. anaerobic respiration
c. ATP synthase
d. chemiosmotic gradient
e. citric acid cycle
f. cristae
g. electron transport chain
h. FADH2
i. glycolysis
j. Krebs cycle
k. NADH
l. pyruvate
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.3: Vocabulary II
Name
Class
Date
Fill in the blank with the appropriate term.
1. The reactions of cellular respiration can be grouped into three stages:
cycle, and electron transport.
, the
2. Cellular respiration in the absence of oxygen is called
respiration.
3. The last two stages of cellular respiration occur in the
.
4. Most of the ATP is produced in stage
5.
of cellular respiration.
is the final electron acceptor at the end of the electron transport chain, when water is formed.
6. During glycolysis, enzymes split a molecule of glucose into two molecules of
7.
releases the energy in glucose to make ATP.
8. During the Krebs cycle, energy is captured in molecules of
9.
,
, and FADH2 .
is the molecule that enters the Krebs cycle.
10. During glycolysis,
11.
.
molecules of ATP are used, and
molecules of ATP are made.
is the enzyme that produces ATP during the final stage of cellular respiration.
12. In all three stages of aerobic respiration, up to
molecule of glucose.
molecules of ATP may be produced from a single
Lesson 4.3: Critical Writing
Name
Class
Date
Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences.
Discuss why photosynthesis and cellular respiration can be described as a cycle.
54
Photosynthesis Versus Cellular Respiration
Directions: Review the information in Chapter 4 of the CK-­‐12 Interactive Biology book. Use the following Venn diagram to compare and contrast photosynthesis and cellular respiration. Photosynthesis Cellular Respiration 55
Name:
Date:
Period:
Connections Between Cellular Respiration and Photosynthesis
Directions: Use your knowledge of photosynthesis and cellular respiration to complete the following graphic organizers. Include the reactants and products of each process. 56
Topic 5: Cellular Energy (Photosynthesis and
Respiration)
Photosynthesis
Plants:

Autotrophs – they make their own sugars during photosynthesis = Producers - Produce food for all other
organisms
Animals:

Heterotrophs – must get their sugars (carbohydrates) for energy from other sources = Consumers – Consume the
food provided by plants
Sun
Ultimate source of energy because it provides the energy for the plants which is then passed down to other organisms
Photosynthesis
 The process by which plants convert the sun’s energy, water and carbon dioxide to sugar and oxygen (a byproduct)
 Takes place in the chloroplasts
 Chlorophyll is the molecule that receives the sun’s energy
 Chloroplasts are in the mesophyll cells of the leaves and stems (green parts) just below the surface of the leaf (or
stem)
There are two major reactions in photosynthesis
1. Light Dependent reactions
a. Aka Light Reactions
b. Aka photolysis
c. Light energy is absorbed by chlorophyll, which uses the energy to split water. Oxygen is released to the
outside of the cell, the “H” part of H2O is carried to the dark reactions with NADPH
d. Some ATP (energy) is made here—will be used up in Light Independent reactions
2. Light Independent reactions
a. Aka Dark Reactions
b. Aka Carbon fixation (Calvin Cycle)
c. CO2 from the outside is combined with the “H” part of NADPH to make sugars for the cell
i. NADP+ goes back to light dependent reactions
d. ATP is used to combine the CO2 and H
i. ADP goes back to light dependent reactions
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Respiration
Cellular respiration occurs in the mitochondria of eukaryotic organisms. It is composed of three major steps
1. Glycolysis -- glucose is split into 2 3-carbon compounds and a small amount of energy is released.
a. Cytoplasm of all cells
2. Kreb’s cycle – takes 3-carbon compounds and breaks them down into carbon dioxide
a. Inner part of mitochondria (matrix)
3. Electron transport chain – takes electron carriers and materials to create a concentration gradient that
ultimately creates ATP
a. Inner folds of mitochondria (cristae)




Respiration - I. Breathing [external respiration]; II. oxidative metabolism in which an inorganic
substance, usually oxygen, is used as the final electron [hydrogen] acceptor; compare with fermentation.
Glycolysis - Metabolic pathway found in the cytoplasm that participates in aerobic cellular respiration
and fermentation; it converts glucose to two molecules of pyruvate.
Glucose - Six-carbon sugar that organisms degrade as a source of energy during cellular respiration.
Energy - Capacity to do work and bring about change; occurs in a variety of forms.
In the absence of oxygen, some organisms will use the products of glycolysis and go through fermentation.
A. Alcoholic fermentation—makes alcohol and CO2 as the byproducts. Creates no ATP, but “refreshes” carriers so
glycolysis can continue
B. Lactic acid fermentation—makes lactic acid as the byproduct. Creates no ATP, but “refreshes” carriers so
glycolysis can continue
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39. What are the raw materials for photosynthesis?
40. What product of photosynthesis is used in cellular respiration?
41. What is the advantage of having a folded inner membrane in the mitochondria?
42. What is the energy for photosynthesis?
43. Besides chlorophyll, what other pigments are found in the chloroplasts?
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4.3. Powering the Cell: Cellular Respiration
4.4 Anaerobic Respiration
Lesson 4.4: True or False
Name
Class
Date
Write true if the statement is true or false if the statement is false.
1. Fermentation is the process of making ATP in the presence of oxygen.
2. Aerobic respiration evolved after oxygen was added to Earth’s atmosphere.
3. Anaerobic respiration lets organisms live in places where there is little or no oxygen.
4. Alcoholic fermentation explains why bread dough rises.
5. Fermentation recycles NADP+ .
6. Anaerobic respiration is a very slow process.
7. Some plants and fungi and many bacteria do not need oxygen.
8. Some organisms may not be able to survive in the presence of oxygen.
9. Alcoholic fermentation explains why your muscles are sore after intense exercise.
10. There are three types of fermentation: anaerobic, aerobic, and cellular.
11. Some organisms can use both aerobic and anaerobic respiration.
12. Most living things use glucose to make ATP from oxygen.
13. Bread rises because of alcoholic fermentation.
14. Fermentation allows glycolysis to continue in the absence of oxygen.
15. Anaerobic respiration produces much more ATP than aerobic respiration.
Lesson 4.4: Critical Reading
Name
Class
Date
Read these passages from the text and answer the questions that follow.
Fermentation
An important way of making ATP without oxygen is called fermentation. It involves glycolysis but not the other
two stages of aerobic respiration. Many bacteria and yeasts carry out fermentation. People use these organisms to
make yogurt, bread, wine, and biofuels. Human muscle cells also use fermentation. This occurs when muscle cells
cannot get oxygen fast enough to meet their energy needs through aerobic respiration.
There are two types of fermentation: lactic acid fermentation and alcoholic fermentation. Both types of are described
below.
Lactic Acid Fermentation
In lactic acid fermentation, pyruvic acid from glycolysis changes to lactic acid. In the process, NAD+ forms
from NADH. NAD+ , in turn, lets glycolysis continue. This results in additional molecules of ATP. This type of
fermentation is carried out by the bacteria in yogurt. It is also used by your own muscle cells when you work them
hard and fast.
Did you ever run a race and notice that your muscles feel tired and sore afterward? This is because your muscle cells
used lactic acid fermentation for energy. This causes lactic acid to build up in the muscles. It is the buildup of lactic
acid that makes the muscles feel tired and sore.
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Alcoholic Fermentation
In alcoholic fermentation, pyruvic acid changes to alcohol and carbon dioxide. NAD+ also forms from NADH,
allowing glycolysis to continue making ATP. This type of fermentation is carried out by yeasts and some bacteria. It
is used to make bread, wine, and biofuels.
Alcoholic fermentation produces ethanol and NAD+ . The NAD+ allows glycolysis to continue making ATP.
Have your parents ever put corn in the gas tank of their car? They did if they used gas containing ethanol. Ethanol
is produced by alcoholic fermentation of the glucose in corn or other plants. This type of fermentation also explains
why bread dough rises. Yeasts in bread dough use alcoholic fermentation and produce carbon dioxide gas. The gas
forms bubbles in the dough, which cause the dough to expand. The bubbles also leave small holes in the bread after
it bakes, making the bread light and fluffy.
Questions
1. What is fermentation?
2. Why is NAD+ so important in fermentation?
3. Both lactic acid fermentation and alcoholic fermentation begin with the same molecule. What is that molecule
and where did it come from?
4. Why is bread light and fluffy?
5. Why do your muscles get sore after intense activity?
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4.4. Anaerobic Respiration
Lesson 4.4: Multiple Choice
Name
Class
Date
1. Complete this sentence: Most living things use
a.
b.
c.
d.
to make
from glucose.
oxygen, ATP
ATP, oxygen
NADH, NAD+
oxygen, NAD+
2. Which of the following organisms can perform alcoholic fermentation? (1) yeast, (2) humans, (3) bacteria.
a.
b.
c.
d.
1 only
1 and 2
1 and 3
1, 2, and 3
3. Which of the following is true about anaerobic respiration?
a.
b.
c.
d.
It is a very fast process.
It allows organisms to live in places where there is little or no oxygen.
It evolved before aerobic respiration.
All of the above are true.
4. In alcoholic fermentation
a.
b.
c.
d.
carbon dioxide is released.
NADH is recycled.
lactic acid is produced.
all of the above
5. Fermentation involves which stages of cellular respiration? (1) glycolysis, (2) the Krebs cycle, (3) electron
transport.
a.
b.
c.
d.
1 only
1 and 2
2 and 3
all three stages
6. In lactic acid fermentation
a.
b.
c.
d.
carbon dioxide is released.
NADH is recycled.
lactic acid is produced.
all of the above
7. After intense activity, your muscles feel sore because of
a.
b.
c.
d.
the accumulation of NAD+ .
the accumulation of lactic acid.
the accumulation of ATP.
the accumulation of carbon dioxide.
8. Both alcoholic fermentation and lactic acid fermentation
a.
b.
c.
d.
start with pyruvic acid.
recycle NAD+ from NADH.
allow glycolysis to continue.
all of the above
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Chapter 4. Photosynthesis and Cellular Respiration Worksheets
Lesson 4.4: Vocabulary I
Match the vocabulary word with the proper definition.
Definitions
1. an important way of making ATP without oxygen
2. respiration in the absence of oxygen
3. makes your muscles feel tired and sore after intense exercise
4. recycles during fermentation
5. perform cellular respiration in the presence of oxygen
6. can use lactic acid fermentation for energy
7. can use alcoholic fermentation for energy
8. stage of cellular respiration that occurs with or without oxygen
9. product of glycolysis
10. energy in the cell
11. fermentation in which pyruvic acid from glycolysis changes to lactic acid
12. fermentation in which pyruvic acid changes to alcohol and carbon dioxide
Terms
a. aerobic organisms
b. alcoholic fermentation
c. anaerobic respiration
d. ATP
e. fermentation
f. glycolysis
g. lactic acid
h. lactic acid fermentation
i. muscle cells
j. NAD+
k. pyruvic acid
l. yeast
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4.4. Anaerobic Respiration
Lesson 4.4: Vocabulary II
Name
Class
Date
Fill in the blank with the appropriate term.
1. A way of making
without oxygen is called fermentation.
2. During lactic acid fermentation, NAD+ cycles back to allow
3. Fermentation involves
4. Aerobic respiration evolved after
to continue.
, but not the other two stages of cellular respiration.
was added to Earth’s atmosphere.
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5. In
Chapter 4. Photosynthesis and Cellular Respiration Worksheets
fermentation, pyruvic acid changes to alcohol and carbon dioxide.
6. Organisms that can make ATP without oxygen include some plants and
7. In
fermentation, pyruvic acid from glycolysis changes to lactic acid.
8. The small holes in bread are formed by bubbles of
tion in yeast.
gas, which is produced by alcoholic fermenta-
9. Without oxygen, organisms can just split glucose into
10.
and also of many bacteria.
molecules of pyruvate.
in bread dough use alcoholic fermentation and produce carbon dioxide gas.
11. Aerobic respiration produces much more
12. Most organisms use oxygen to make
than anaerobic respiration.
from glucose.
Lesson 4.4: Critical Writing
Name
Class
Date
Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences.
Compare aerobic and anaerobic respiration, and discuss the advantages of each.
65