chapter 9

Question 1

What is the function of cellular respiration?

Answer 1

to break down glucose or other organic molecules to provide the energy needed to regenerate ATP.

Question 2

What are the reactants and the products of cellular respiration?

Answer 2

the reactants are glucose and oxygen, the products are carbon dioxide, water, and energy

Question 3

In what parts of the cell do the metabolic pathways of cellular respiration take place?

Answer 3

Glycolysis takes place in the cytosol; pyruvate oxidation, citric acid cycle, and oxidative phosphorylation take place in the mitochondria.

Question 4

What are the energetic and/or product outputs of Glycolysis

Answer 4

2 pyruvate, 2 NADH, 2 H+ and 4 ATP

Question 5

What are the energetic and/or product outputs of the Citric acid cycle

Answer 5

2 ATP, 6 NADH, 2 FADH2

Question 6

What are the energetic and/or product outputs of Oxidative phosphorylation

Answer 6

about 26-28 ATP

Question 7

Where does glycolysis occur?

Answer 7

in the cytosol

Question 8

Is glycolysis aerobic?

Answer 8

No, it doesn’t require oxygen

Question 9

What are the two phases of glycolysis?

Answer 9

Energy investment and energy payoff

Question 10

At what phase in glycolysis is energy used?

Answer 10

Energy investment

Question 11

What is the final product of glycolysis?

Answer 11

For each glucose molecule that enters glycolysis, two pyruvates are produced

Question 12

Where in the cell does the citric acid cycle take place?

Answer 12

Inside the mitochondrion

Question 13

Does substrate level phosphorylation occur in the citric acid cycle, how many times per cycle?

Answer 13

Yes, once per cycle

Question 14

What is produced as a result of each cycle of the citric acid cycle?

Answer 14

1 ATP, 3NADH, 1 FADH2, 2 CO2

Question 15

Where in the mitochondria does oxidative phosphorylation occur?

Answer 15

cross the inner membrane

Question 16

What molecules carry electrons to the machinery of oxidative phosphorylation?

Answer 16

NADH

Question 17

Is the process of oxidative phosphorylation aerobic? If so, what does oxygen have to do with the process?

Answer 17

Yes, it is aerobic. Oxygen serves as the final electron acceptor of the electron transport chain.

Question 18

How does the availability of oxygen affect oxidative phosphorylation?

Answer 18

If there isn’t any oxygen then electron transport shuts down and there isn’t the chemical gradient needed to power oxidative phosphorylation. In short, it doesn’t happen

Question 19

Describe chemiosmosis.

Answer 19

Electron transfer in the electron transport chain causes proteins to pump H+ from the mitochondrial matrix to the intermembrane space; The energy stored in a H+ gradient across a membrane couples the redox reactions of the electron transport chain to ATP synthesis; H+ then moves back across the inner membrane, passing through the proton, ATP synthase; ATP synthase uses the exergonic flow of H+ to drive phosphorylation of ATP; This is an example of chemiosmosis, the use of energy in a H+ gradient to drive cellular work

Question 20

Compared to glycolysis and the citric acid cycle, how would you describe the amount of ATP that oxidative phosphorylation produces.

Answer 20

OP produces 90% of the ATP produced by cellular respiration

Question 21

Describe fermentation.

Answer 21

fermentation uses anaerobic substrate-level phosphorylation instead of an electron transport chain to generate ATP

Question 22

What are the reactants and the products of fermentation?

Answer 22

reactants are glucose and products are either 1) ethanal (alcohol) and carbon dioxide or 2) lactic acid