Deck 7: Vital Harvest: Deriving Energy From Food

Question 1

The Krebs cycle extracts most of the energy in a glucose molecule and stores it in:

A)pyruvic acid.
B)ATP.
C)CO₂.
D)NADH.
E)O₂.

Answer 1

D

Question 2

During the Krebs cycle,acetyl CoA covalently binds to oxaloacetate to form citrate,a ________ -carbon molecule.

A)six
B)three
C)five
D)two
E)four

Answer 2

A

Question 3

Cells capture the energy from food and store it in the form of:

A)glucose.
B)ATP.
C)oxygen.
D)heat.
E)carbon dioxide.

Answer 3

B

Question 4

During glycolysis,a glucose molecule will be split into two,three-carbon ________ molecules.

A)acetyl CoA
B)pyruvic acid
C)ATP
D)oxaloacetatic acid

Question 5

There is an energy investment step needed to get glycolysis started,requiring the use of ________ ATPs.

A)zero
B)four
C)two
D)three
E)one

Question 6

When NADH donates its electrons to the electron transport chain,which of the following is true?

A)NADH is reduced to NAD⁺.
B)NADH is oxidized to NADH₂.
C)NADH is reduced to NADH₂.
D)NADH is oxidized to NAD⁺.

Question 7

The majority of ATP in aerobic respiration is produced by:

A)the Krebs cycle.
B)glycolysis.
C)the electron transport chain.

Question 8

What does oxygen allow humans to do?

A)breathe
B)produce food
C)digest food
D)produce ATP from food

Question 9

In which of the following reactions is reduction taking place?

A)NAD⁺ → NADH
B)FADH → FAD⁺
C)NADH → NAD⁺

Question 10

Why do biologists believe glycolysis evolved before the Krebs cycle and the electron transport chain?

A)Glycolysis occurs in the mitochondria, which all organisms have.
B)Glycolysis requires oxygen, which was one of the first elements on Earth.
C)All organisms use glycolysis; not all use the Krebs cycle and the electron transport chain.
D)Glycolysis is the most efficient at producing energy.

Question 11

The three main products of glycolysis are:

A)ATP, NAD⁺, and CO₂.
B)ATP, pyruvic acid, and CO₂.
C)ATP, NADH, and CO₂.
D)ATP. NADH, and pyruvic acid.
E)NAD⁺, pyruvic acid, and CO₂.

Question 12

During cellular respiration,what molecule collects the majority of the electrons from the food that we eat?

A)CO₂
B)FAD⁺
C)NAD⁺
D)glucose
E)ATP

Question 13

How many pyruvic acid molecules are generated during the oxidation of one glucose molecule during cellular respiration?

A)three
B)two
C)zero
D)one
E)four

Question 14

The term aerobic means:

A)ATP-dependent.
B)carbon dioxide-dependent.
C)oxygen-dependent.
D)oxygen-independent.

Question 15

Glycolysis produces how many molecules of NADH?

A)one
B)two
C)three
D)four

Question 16

Oxidation involves the ________ ,and reduction involves the

A)gain of oxygen; loss of oxygen
B)loss of oxygen; gain of oxygen
C)loss of electrons; gain of electrons
D)gain of electrons; loss of electrons

Question 17

Glycolysis occurs in the cell's:

A)cytosol.
B)mitochondria.
C)Golgi apparatus.
D)plasma membrane.
E)nucleus.

Question 18

Energy is required to link a phosphate group to ADP to make ATP.Where does the energy come from?

A)vitamins
B)enzymes
C)food we eat
D)breathing

Question 19

Which of the following is an example of a molecule being oxidized?

A)oxygen being converted into H₂O
B)pyruvate being converted into lactic acid
C)FAD being converted into FADH₂
D)NADH being converted into NAD⁺

Question 20

The chemical equation that summarizes the process of cellular respiration is:

A)C₆H₁₂O₆ + 6CO₂ + 36ADP + 36P → 6O₂ + 6H₂O + 36ATP
B)6O₂ + 6H₂O + 36 ATP → C₆H₁₂O₆ + O₂ + 36ADP + 36P
C)C₆H₁2O₆ + 6O₂ + 36ATP → 6O₂ + 6H₂O + 36 ADP + 36P
D)C₆H₁₂O₆ + 6O₂ + 36ADP + 36P → 6O₂ + 6H₂O + 36ATP

Question 21

When acetyl CoA enters the Krebs cycle,the first molecule produced is:

A)citric acid.
B)α-ketoglutaric acid.
C)succinic acid.
D)malic acid.
E)oxaloacetatic acid.

Question 22

The enzymes used by the electron transport chain are located:

A)in the cytosol.
B)in the outer membrane of the mitochondrion.
C)in the inner membrane of the mitochondrion.
D)between the inner and outer membranes of the mitochondrion.

Question 23

The electron transport chain is used during which of the following processes?

A)lactate fermentation
B)aerobic cellular respiration
C)glycolysis
D)alcoholic fermentation

Question 24

During electron transport,how many ATP molecules are produced per NADH molecule and FADH₂ molecule?

A)three per NADH and three per FADH₂
B)two per NADH and two per FADH₂
C)three per NADH and two per FADH₂
D)two per NADH and three per FADH₂

Question 25

Which of the following molecules is produced in the intermediate step between glycolysis and the Krebs cycle?

A)ATP
B)oxaloacetate
C)pyruvic acid
D)acetyl CoA
E)citric acid

Question 26

How many NADH molecules are created during one turn of the Krebs cycle? (Assume the Krebs cycle begins with one acetyl CoA molecule.)

A)four
B)six
C)one
D)three
E)eight

Question 27

How many turns of the Krebs cycle are needed to completely break down one molecule of glucose?

A)one
B)two
C)three
D)four

Question 28

The enzyme that creates ATP during electron transport is called:

A)ADP phosphotransferase.
B)ATP creatase.
C)ATP polymerase.
D)ATP synthase.

Question 29

Which of the following are electron carriers produced by the Krebs cycle?

A)ATP and FADH₂
B)ATP and CO₂
C)NADH and ATP
D)NADH and FADH₂

Question 30

Glycolysis occurs in the ________,the Krebs cycle occurs in the ________,and the electron transport chain occurs in the ________ membrane.

A)mitochondria; mitochondria; mitochondrial
B)cytoplasm; mitochondria; mitochondrial
C)mitochondria; cytoplasm; plasma
D)cytoplasm; cytoplasm; plasma
E)cytoplasm; mitochondria; plasma

Question 31

Certain drugs prevent the formation of a hydrogen ion gradient across the inner mitochondrial membrane.What is the most likely consequence?

A)Most ATP production will stop, and the cell will die.
B)ATP production will increase.
C)Glycolysis will stop.
D)Fermentation will stop.

Question 32

The end products that come out of the Krebs cycle include all of the following except:

A)NADH.
B)pyruvic acid.
C)FADH₂.
D)CO₂.
E)ATP.

Question 33

When glucose is the fuel source,what is the correct sequence of stages in cellular respiration?

A)glycolysis, Krebs cycle, electron transport
B)electron transport, Krebs cycle, glycolysis
C)Krebs cycle, glycolysis, electron transport
D)electron transport, glycolysis, Krebs cycle
E)Krebs cycle, electron transport, glycolysis

Question 34

Which of the following statements concerning the electron transport chain is false?

A)The final electron acceptor is oxygen.
B)Each NADH yields three ATP molecules.
C)Each FADH₂ yields two ATP molecules.
D)The electron transport chain will work whether oxygen is present or not.

Question 35

The enzymes used by the Krebs cycle are located:

A)in the cytosol.
B)in the inner compartment of the mitochondrion.
C)attached to the inner mitochondrial membrane.
D)between the inner membrane and outer mitochondrial membrane.

Question 36

Eukaryotic cells require oxygen to:

A)enter the Krebs cycle as an intermediate.
B)perform fermentation.
C)breathe.
D)serve as an electron acceptor in the electron transport chain.
E)start glycolysis.

Question 37

A total of four ATP molecules have to be used by aerobic respiration in eukaryotic cells.Where are these four ATP molecules used?

A)One molecule is used to start glycolysis, and three are used to move NADH made during glycolysis into the mitochondria.
B)Three molecules are used to start glycolysis, and one is used to move NADH made during glycolysis into the mitochondria.
C)Two molecules are used to start glycolysis, and two are used to move NADH made during glycolysis into the mitochondria.
D)All four molecules are used to start glycolysis.
E)All four molecules are used to move NADH made during glycolysis into the mitochondria.

Question 38

Oxygen is reduced to water in the cell's:

A)nucleus.
B)mitochondria.
C)cytoplasm.
D)Golgi apparatus.
E)plasma membrane.

Question 39

How many NADH are produced in the Krebs cycle for each glucose molecule used?

A)one
B)three
C)six
D)eight

Question 40

All of the following occur as glucose moves through glycolysis and the Krebs cycle except:

A)NAD⁺ is converted to NADH.
B)CO₂ is released.
C)actely CoA is removed to form pyruvate.
D)acetyl CoA enters the Krebs cycle.

Question 41

In order for one molecule to be oxidized,another molecule must be reduced.

Question 42

Before proteins can be used for cellular respiration,they must be broken down into:

A)pyruvate.
B)fatty acids.
C)amino acids.
D)glucose.

Question 43

Organisms exist that can survive using only glycolysis.

Question 44

During cellular respiration:

A)glucose is reduced and oxygen is oxidized.
B)glucose is oxidized and oxygen is reduced.
C)oxygen oxidizes glucose directly.
D)both glucose and oxygen get reduced.

Question 45

Proteins are not oxidized by aerobic respiration.

Question 46

Adding phosphate to ADP to form ATP requires an input of energy.

Question 47

What is the final net number of ATP molecules that can be produced per glucose molecule by cellular respiration?

A)36
B)4
C)8
D)2
E)38

Question 48

Which of the following statements is true of aerobic respiration?

A)Fats proceed through aerobic respiration in exactly the same manner as glucose.
B)Proteins proceed through aerobic respiration in exactly the same manner as glucose.
C)Glucose will be completely broken down even if oxygen is not present.
D)Glucose, fats, and proteins can be oxidized by aerobic respiration

Question 49

Before starch can be used for cellular respiration,it must be broken down into:

A)pyruvate.
B)fatty acid.
C)oxaloacetatic acid.
D)amino acids.
E)glucose.

Question 50

What role do hydrogen ions (H⁺)play in the electron transport chain?

A)They are pumped across the mitochondrial inner membrane against their concentration gradient (to where their concentration is high); as the H⁺ ions flow back to where their concentration is low, they drive ATP synthase to form ATP.
B)They are pumped across the mitochondrial inner membrane against their concentration gradient (to where their concentration is low); as the H⁺ ions flow back to where their concentration is high, they drive ATP synthase to form ATP.
C)They add phosphate groups on ADP to form ATP.
D)They transfer electrons to the electron transport chain.

Question 51

What is the energy source used to drive ATP synthase to produce ATP?

A)glucose coming across the mitochondrial inner membrane
B)H⁺ ions flowing across the mitochondrial inner membrane
C)acetyl CoA coming across the mitochondrial inner membrane
D)NADH coming across the mitochondrial inner membrane
E)electrons flowing through the electron transport chain

Question 52

The majority of ATP produced during aerobic respiration is produced during glycolysis.

Question 53

A molecule that has gained electrons has been ________.

Question 54

A molecule that has lost electrons has been reduced.

Question 55

The Krebs cycle must turn six times for each glucose molecule.

Question 56

Electrons lose energy as they pass down the electron transport chain.What is this energy used for?

A)to power hydrogen ion pumps
B)to link oxygen to hydrogen ions
C)to power water pumps
D)to directly power ATP synthase

Question 57

Glycolysis probably evolved before the Krebs cycle.

Question 58

In order for a fat to be used for energy,it must first be broken down into:

A)amino acids.
B)glucose.
C)fatty acids and sugars.
D)fatty acids and glycerol.

Question 59

Which of the following types of foods can be oxidized by aerobic respiration?

A)only glucose
B)only fats
C)only proteins
D)only glucose and fats
E)glucose, fats, and proteins

Question 60

Refer to the figure below, and then answer the question that follows.

As electrons move through the electron transport chain,which of the following occurs?

A)Electrons are pumped from the inner compartment of the mitochondrion to the outer compartment of the mitochondrion.
B)Hydrogen ions move down their concentration gradient from the inner compartment of the mitochondrion to the outer compartment of the mitochondrion.
C)Energy from ATP is used to pump hydrogen ions across the inner membrane of the mitochondrion.
D)ATP is synthesized from ADP and P as hydrogen ions flow down the electron transport chain.
E)Hydrogen ions are pumped from the inner compartment of the mitochondrion to the outer compartment of the mitochondrion.

Question 61

Human babies and animals adapted to the cold are able to maintain their body temperatures because of the presence of brown fat.The mitochondria in brown fat have a protein in them called thermogenin,which allows the flow of hydrogen ions back through the inner mitochondrial membrane (bypassing the ATP synthase).Based on this and your understanding of cellular respiration,propose a mechanism by which brown fat helps keep babies and other animals warm.

Question 62

Cyanide is a deadly poison that reacts with hemoglobin in our blood and prevents it from binding oxygen.Cyanide also binds to a molecule in the electron transport chain and blocks the flow of electrons down the chain.Explain why both these mechanisms will stop ATP synthesis.

Question 63

________ is the first product of the Krebs cycle.

Question 64

One of the most common misconceptions about cellular respiration is that we inhale oxygen and that this oxygen is converted to carbon dioxide,which we exhale.Explain what happens to the oxygen we inhale during cellular respiration.Then explain where the carbon dioxide we exhale comes from in cellular respiration.

Question 65

When fats are metabolized by aerobic respiration,they are first split into ________ and ________ molecules.

Question 66

Refer to the figure below, and then answer the question that follows.

Which stage or stages of aerobic respiration require both NAD⁺ and ADP as reactants?

A)glycolysis
B)the Krebs cycle
C)the electron transport chain
D)the Krebs cycle and the electron transport chain
E)glycolysis and the Krebs cycle

Question 67

During aerobic respiration,the final electron acceptor is ________.

Question 68

The electron transport chain occurs in the ________ of the mitochondria.

Question 69

As you know,all living things require a source of nutrients.Using animals as an example,explain what these nutrients are used for once they leave the digestive tract.

Question 70

________ means "sugar splitting."

Question 71

The three-carbon ________ combines with coenzyme A to form ________.

Question 72

Mitochondria can be isolated from cells and their production of ATP measured.You want to identify the mechanism of ATP production,so you isolate mitochondria,remove the outer membrane,and place them in a high pH solution.What will happen to the ATP production if you start to lower the pH by adding hydrogen ions to the solution?

Question 73

The most important electron carrier in cellular respiration is ________.