Ch 7-2

Question 1

What process allows organisms to create energy in the absence of oxygen?

Answer 1

Fermentation

Question 2

What molecule is oxidized in the citric acid cycle?

Answer 2

Pyruvate

Question 3

What is produced during steps 7 and 10 of glycolysis?

Answer 3

ATP.

Question 4

What process occurs in the mitochondria to harvest energy from pyruvate?

Answer 4

Pyruvate oxidation.

Question 5

What is the final electron acceptor in aerobic respiration?

Answer 5

Oxygen

Question 6

How many turns of the citric acid cycle occur for every glucose molecule?

Answer 6

2 turns

Question 7

What are the two forms of fermentation?

Answer 7

Lactic acid fermentation and alcohol fermentation.

Question 8

What is reduced to FADH2 during the citric acid cycle?

Answer 8

FAD

Question 9

What is the approximate efficiency of cellular respiration in terms of energy extraction from glucose?

Answer 9

33%

Question 10

What cycle is also known as the Kreb’s cycle?

Answer 10

citric acid cycle.

Question 11

Aerobic respiration yields 2 ATP.

Answer 11

False (yields 32 ATP).

Question 12

In fermentation, NAD+ is regenerated to continue ATP production.

Answer 12

TRUE

Question 13

Pyruvate is fully oxidized in glycolysis.

Answer 13

False (pyruvate oxidation occurs after glycolysis).

Question 14

FAD is reduced to FADH2 during glycolysis.

Answer 14

False (this occurs in the citric acid cycle).

Question 15

Citric acid cycle takes place in the mitochondria of prokaryotic cells

Answer 15

False (prokaryotes do not have mitochondria).

Question 16

Oxygen determines whether a cell will undergo aerobic respiration or fermentation

Answer 16

TRUE

Question 17

Glycolysis produces 4 ATP per glucose molecule.

Answer 17

False (it produces 2 net ATP).

Question 18

Pyruvate still retains over 75% of the energy from glucose after glycolysis

Answer 18

TRUE

Question 19

Lactic acid fermentation occurs in muscle cells.

Answer 19

TRUE

Question 20

The citric acid cycle generates 1 atp per turn

Answer 20

True

Question 21

What is the primary role of NADH in cellular respiration?
(a) Energy storage
(b) Electron carrier
(c) Structural support

Answer 21

B) electron carrier

Question 22

How many molecules of CO2 are produced per turn of the citric acid cycle?
(a) 1
(b) 2
(c) 3

Answer 22

B) 2

Question 23

What enzyme converts pyruvate to acetyl-CoA?
(a) Hexokinase
(b) Pyruvate dehydrogenase
(c) ATP synthase

Answer 23

b) Pyruvate dehydrogenase.

Question 24

What is the total ATP yield from one molecule of glucose in cellular respiration?
(a) 32
(b) 12
(c) 2

Answer 24

A) 32

Question 25

What is regenerated at the end of the citric acid cycle? (a) ATP (b) Oxaloacetate (c) Pyruvate

Answer 25

B) ocaloacetate

Question 26

Where does pyruvate oxidation occur in eukaryotes? (a) Cytosol (b) Mitochondrial matrix (c) Nucleus

Answer 26

B) mitochondrial matrix

Question 27

Which of the following is NOT a product of the citric acid cycle? (a) ATP (b) NADPH (c) CO2

Answer 27

C) 2

Question 28

How many molecules of ATP does fermentation produce per glucose molecule? (a) 32 (b) 10 (c) 2

Answer 28

C) 2

Question 29

What happens during steps 1 and 3 of glycolysis? (a) ATP is produced (b) ATP is consumed (c) Water is released

Answer 29

B) atp is consumed

Question 30

Which molecule is an electron carrier similar to NAD+? (a) FAD (b) Glucose (c) CO2

Answer 30

A) FAD

Question 31

What is the main purpose of fermentation? (a) Produce ATP (b) Recycle NADH (c) Create oxygen

Answer 31

B) recycle NADH

Question 32

Which metabolic pathway happens first in glucose metabolism? a) Citric acid cycle (b) Glycolysis (c) Pyruvate oxidation

Answer 32

B) glycolysis

Question 33

Which molecule starts the citric acid cycle? (a) Pyruvate (b) Oxaloacetate (c) Acetyl-CoA

Answer 33

C) acetyl-CoA

Question 34

How many NADH molecules are produced per turn of the citric acid cycle? (a) 1 (b) 2 (c) 3

Answer 34

C) 3

Question 35

What happens to pyruvate under anaerobic conditions? a) It is oxidized (b) It is fermented (c) It is turned into glucose

Answer 35

B) it is fermented

Question 36

What determines whether cells will undergo aerobic respiration or fermentation? (a) NADH levels (b) Oxygen availability (c) ATP demand

Answer 36

B) oxygen availability

Question 37

How many ATP molecules are produced directly in glycolysis? (a) 2 (b) 4 (c) 6

Answer 37

A) 2

Question 38

What process produces the majority of ATP during cellular respiration? (a) Glycolysis (b) Citric acid cycle (c) Oxidative phosphorylation

Answer 38

C) oxidative phosphorylation

Question 39

Which of the following is not required for glycolysis? (a) Glucose (b) Oxygen (c) ATP

Answer 39

B) oxygen

Question 40

What type of cells can perform lactic acid fermentation? (a) Bacteria (b) Yeast (c) Muscle cells

Answer 40

C) muscle cells

Question 41

In the absence of oxygen, which of the following can still occur? (a) Glycolysis (b) Citric acid cycle (c) Oxidative phosphorylation

Answer 41

A) glycolysis

Question 42

How many carbons are in acetyl-CoA? (a) 2 (b) 3 (c) 4

Answer 42

A) 2

Question 43

What molecule serves as the primary electron donor in cellular respiration? (a) Oxygen (b) NADH (c) Glucose

Answer 43

C) glucose

Question 44

What is the name of the enzyme that converts ADP to ATP during oxidative phosphorylation? (a) ATP synthase (b) Pyruvate kinase (c) Hexokinase

Answer 44

A) ATP synthase