Ch. 8

Question 1

Define aerobic catabolism

Answer 1

Breakdown pathways requiring oxygen

Question 2

Define anaerobic catabolism

Answer 2

Breakdown pathways that don’t require oxygen

Question 3

Define glycolysis

Answer 3

Reactions that convert glucose to pyruvic acid

Question 4

Define the Krebs cycle

Answer 4

Oxidation of acetyl-CoA to reduce NAD+ and FAD+

Question 5

Define the electron transport chain

Answer 5

Series of compounds in the mitochondria that passes electrons to O2 and forms a proton gradient

Question 6

Define oxidative phosphorylation

Answer 6

Formation of ATP using the proton gradient formed from the ETC

Question 7

Define the chemiosmotic hypothesis

Answer 7

States that the ETC pumps protons into the mitochondrial intermembrane space to activate ATP synthase to produce ATP

Question 8

Define gluconeogenesis

Answer 8

Synthesis of glucose from pyruvic acid

Question 9

Define steady-state

Answer 9

Method of production that can continue using readily-supplied substrates (aerobic conditions)

Question 10

Define non steady-state

Answer 10

Method of production that is self-limiting through depleting substrates or end-product accumulation (anaerobic conditions)

Question 11

The number of offspring fathered by male collared lizards is positively correlated by its _______________, or energy utilization.

Answer 11

burst speed

Question 12

Define reduction

Answer 12

Gain of electrons

Question 13

Define oxidation

Answer 13

Loss of electrons

Question 14

Products of glycolysis

Answer 14

2 ATP, 2 NADH2, 2 pyruvic acid

Question 15

Products of the Krebs cycle

Answer 15

2 ATP, 8 NADH2, 2 FADH2

Question 16

Products of oxidative phosphorylation

Answer 16

25 ATP

Question 17

Where does glycolysis occur in the cell?

Answer 17

cytoplasm

Question 18

Where does the Krebs cycle occur in the cell?

Answer 18

mitochondria

Question 19

Where does the ETC occur in the cell?

Answer 19

mitochondrial inner membrane

Question 20

Which complex of the ETC does not contribute to the proton gradient?

Answer 20

II

Question 21

Net ATP from aerobic catabolism of glucose

Answer 21

29 ATP

Question 22

Explain the inefficiency involved in oxidative phosphorylation.

Answer 22

Uncoupling protein 1 (UCP1) is also affected by the proton gradient, producing heat instead of ATP.

Question 23

How does anaerobic catabolism differ from aerobic catabolism in the cell geographically?

Answer 23

Anaerobic catabolism doesn’t enter the mitochondria

Question 24

In anaerobic catabolism, lactic acid is produced from pyruvic acid to restore ____.

Answer 24

NAD+

Question 25

When oxygen is available, lactic acid can either enter _________________ or ______________.

Answer 25

gluconeogenesis; Krebs cycle

Question 26

Name the two phosphagens that support anaerobic metabolism

Answer 26

Creatine phosphate and arginine phosphate

Question 27

Define hypoxia

Answer 27

Low levels of oxygen in tissues

Question 28

Define anoxia

Answer 28

Absence of oxygen in tissues

Question 29

One approach to conservation of fish populations is to release unwanted fish accidentally caught in trawling nets. Such fish often have very high concentrations of lactic acid in their bodies. Why do you think they have these high concentrations of lactic acid, and how might their survival after release be affected by their condition?

Question 30

Outline the chemiosmotic hypothesis for the mechanism by which oxidative phosphorylation is coupled with electron transport. How does uncoupling occur in tissues with uncoupling protein 1 (UCP1)? Under what circumstances would uncoupling be disadvantageous, and under what circumstances might it be advantageous?

Question 31

Using two or three carefully chosen examples, illustrate the point that during physical activity, behavior and biochemistry are intimately linked, such that an animal’s exercise performance depends on the mechanisms that are making ATP for the exercise.

Question 32

Why is it important to distinguish temporary electron acceptors in cells from final electron acceptors? What are the unique advantages of O2 as an electron acceptor?

Question 33

Why does an oxygen deficit occur at the start of submaximal exercise in vertebrates? What are the mechanisms of ATP production during the oxygen deficit phase, and how is ATP made in the ensuing pay-as-you-go phase?