Fermentation

Question 1

To obtain energy from starch and glycogen, the body must begin by

Answer 1

hydrolyzing both starch and glycogen to glucose

Question 2

Yeasts can produce ATP by either fermentation or oxidative phosphorylation; thus, they are

Answer 2

facultative anaerobes

Question 3

Bacteria that are unable to survive in the presence of oxygen are called

Answer 3

obligate anaerobes

Question 4

T/F: Once lactic acid is formed in fermentation, it is excreted by the body as waste

Answer 4

false

Question 5

When proteins are used as a source of energy for the body, the proteins

Answer 5

are converted mainly into intermediates of glycolysis or the citric acid cycle

Question 6

An organism is discovered that consumes a considerable amount of sugar, yet does not gain much weight when denied air. Curiously, the consumption of sugar increases as air is removed from the organism’s environment, but the organism seems to thrive even in the absence of air. When returned to normal air, the organism does fine. Which of the following best describes the organism?

Answer 6

it is a facultative anaerobe

Question 7

When a cell uses fatty acid for aerobic respiration, it first hydrolyzes fats to

Answer 7

glycerol and fatty acids

Question 8

There is a need to break down more food molecule than simple sugars. Such processes tend to be

Answer 8

catabolic and exergonic

Question 9

Catabolism of proteins, lipids, and carbohydrates can result in a 2-carbon molecule that enters the Krebs cycle. What is the molecule?

Answer 9

acetic acid or acetyl CoA

Question 10

Muscle cells in oxygen deprivation convert pyruvate to _____ and in this step gain ______.

Answer 10

lactate……NAD+

Question 11

In fermentation, _____ is ______.

Answer 11

NADH……oxidized

Question 12

What % of total energy is transferred from the original glucose molecule that goes through either type of fermentation process?

Answer 12

2

Question 13

Muscle soreness associated with strenuous exercise is at least partly due to

Answer 13

the presence of lactate produces during fermentation in muscle cells

Question 14

Carbon skeletons to be broken down during cellular respiration can be obtained from

Answer 14

proteins, lipids, and polysaccharides

Question 15

Of the 20 common amino acids,

Answer 15

only 11 are synthesized in the human body, the other 9 must be supplied by the diet

Question 16

When an organism such as a yeast lives by fermentation, it converts the pyruvate from glycolysis into a different compound, such as alcohol. Why doesn’t it secrete the pyruvate directly?

Answer 16

the conversion is needed to regenerate the NAD+ consumed during glycolysis

Question 17

What must a muscle cell do to keep contracting?

Answer 17

regenerate ATP at a very fast rate

Question 18

If you consume 1 g of each of the following, which will yield the most ATP?

Answer 18

fat

Question 19

Some friends are trying to make wine in their basement. They’ve added yeast to a sweet grape juice mixture and have allowed the yeast to grow. After several days they find that sugar levels in the grape juice have dropped, but there’s no alcohol in the mixture. The most likely explanation is that

Answer 19

the mixture needs less oxygen, because yeast only produce alcohol in the absence of oxygen

Question 20

T/F: Fermentation is usually thought of as a process associated more with unicellular rather than multicellular organisms.

Answer 20

true