Chapter 7 BIOL 131

Question 1

The energy currency used by cells is ________.

Answer 1

ATP

Question 2

A reducing chemical reaction ________.

Answer 2

adds an electron to the substrate

Question 3

During the second half of glycolysis, what occurs?

Answer 3

ATP is made

Question 4

What is removed from pyruvate during its conversion into an acetyl group?

Answer 4

carbon dioxide

Question 5

What do the electrons added to NAD+ do?

Answer 5

They go to another pathway for ATP production

Question 6

GTP or ATP is produced during the conversion of ________.

Answer 6

succinyl CoA into succinate

Question 7

How many NADH molecules are produced on each turn of the citric acid cycle?

Answer 7

three

Question 8

What compound receives electrons from NADH?

Answer 8

ubiquinone

Question 9

Chemiosmosis involves ________.

Answer 9

the movement of hydrogen ions across a mitochondrial membrane

Question 10

Which of the following fermentation methods can occur in animal skeletal muscles?

Answer 10

lactic acid fermentation

Question 11

A major connection for sugars in glycolysis is ________.

Answer 11

fructose-1,6-bisphosphate

Question 12

Beta-oxidation is ________.

Answer 12

the breakdown of fatty acids

Question 13

The effect of high levels of ADP is to ________ in cellular respiration.

Answer 13

increase the activity of specific enzymes

Question 14

The control of which enzyme exerts the most control on glycolysis?

Answer 14

phosphofructokinase

Question 15

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

Answer 15

c. glycolysis

Question 16

The Immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the ________.

Answer 16

H+ movement down its concentration gradient

Question 17

In mitochondria, exergonic redox reactions ________.

Answer 17

provide the energy that establish the proton gradient

Question 18

The final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is ________.

Answer 18

oxygen

Question 19

What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+&raquo_space;> lactate + NAD+?

Answer 19

NAD+

Question 20

Most CO2 from catabolism is released during ________.

Answer 20

the citric acid cycle

Question 21

What is the main function of catabolic pathways?

Answer 21

The breakdown (catabolism) of organic molecules is exergonic.

Question 22

What does aerobic respiration consume and yield?

Answer 22

Consumes organic molecules and O2 and yields ATP.

Question 23

What is fermentation?

Answer 23

A partial degradation of sugars that occurs without O2.

Question 24

What characterizes anaerobic respiration?

Answer 24

Similar to aerobic respiration but consumes compounds other than O2.

Question 25

Define oxidation in biochemical terms.

Answer 25

Loss of electrons.

Question 26

Define reduction in biochemical terms.

Answer 26

Gain of electrons.

Question 27

True or False: Oxidation and reduction always occur together.

Answer 27

True.

Question 28

What is the reactant that is reduced called?

Answer 28

Oxidizing agent.

Question 29

What is the reactant that is oxidized called?

Answer 29

Reducing agent.

Question 30

What is the ΔG value for the combustion or metabolism of glucose?

Answer 30

ΔG = –686 kcal/mol.

Question 31

List the three metabolic pathways that harvest glucose energy.

Answer 31

* Glycolysis * Cellular respiration * Fermentation

Question 32

What does glycolysis convert glucose into?

Answer 32

Pyruvate.

Question 33

What does cellular respiration convert pyruvate into?

Answer 33

H2O, CO2, and ATP.

Question 34

What does fermentation convert pyruvate into?

Answer 34

Lactic acid or ethanol, CO2, and ATP.

Question 35

What happens if O2 is present during glucose metabolism?

Answer 35

Glycolysis is followed by the 3 stages of cellular respiration.

Question 36

Name the three stages of cellular respiration.

Answer 36

* Pyruvate oxidation * Citric acid cycle * Oxidative phosphorylation

Question 37

What happens if O2 is absent during glucose metabolism?

Answer 37

Glycolysis is followed by fermentation.

Question 38

What do REDOX reactions transfer?

Answer 38

Electrons and energy.

Question 39

What is the role of the coenzyme NAD+ in redox reactions?

Answer 39

NAD+ is a key electron carrier.

Question 40

What are the two forms of NAD+?

Answer 40

* NAD+ (oxidized) * NADH (reduced)

Question 41

What is substrate-level phosphorylation?

Answer 41

Direct transfer of phosphate groups during glycolysis.

Question 42

What links glycolysis to the citric acid cycle?

Answer 42

Pyruvate oxidation ('grooming').

Question 43

What is produced during pyruvate oxidation?

Answer 43

Acetyl CoA and CO2.

Question 44

What are the inputs of the citric acid cycle?

Answer 44

* Acetyl CoA * Water * NAD+ * FAD * GDP

Question 45

What are the outputs of the citric acid cycle?

Answer 45

* CO2 * NADH * FADH2 * GTP

Question 46

What occurs during anaerobic conditions?

Answer 46

Glycolysis needs a final electron acceptor to replenish NAD+.

Question 47

What is lactic acid fermentation?

Answer 47

Pyruvate is the electron acceptor converting glucose to lactate.

Question 48

What is alcoholic fermentation?

Answer 48

Acetaldehyde is the electron acceptor converting glucose to ethanol and CO2.

Question 49

How do metabolic pathways interrelate?

Answer 49

Through shared substances and enzymatic regulation.

Question 50

What are anabolic pathways?

Answer 50

Biosynthesis where the body uses small molecules to build other substances.

Question 51

Fill in the blank: The body uses small molecules to build other substances in _______.

Answer 51

[anabolic pathways]