Carbohydrates and Glycolysis

Question 1

All monosaccharides contain a _______ group.

Answer 1

Carbonyl.

Question 2

What are the two possible carbonyl groups for a monosaccharide?

Answer 2

Ketone or aldehyde.

Question 3

Which enantiomer is found in nature - D or L glucose?

Answer 3

D-glucose.

Question 4

Which is more common - beta-D-glucose or alpha-D-glucose?

Answer 4

Beta-D-glucose.

Question 5

What is sucrose made of?

Answer 5

A glucose and a fructose.

Question 6

_________ is a branched form of _________.

Answer 6

Amylopectin is a branched form of amylose.

Question 7

Starch is generally 25% ______ and 75% _______.

Answer 7

25% amylose, 75% amylopectin.

Question 8

What is the polymerised version of glucose used for storage called?

Answer 8

Glycogen.

Question 9

Where is glycogen stored?

Answer 9

Muscle and liver cells.

Question 10

What is a homopolysaccharide?

Answer 10

Formed by at least 6 identical monosaccharides.

Question 11

In a low energy state, a cell has a lot of ADP and low ATP. True or false?

Answer 11

True.

Question 12

What accumulates at a very low energy state?

Answer 12

AMP.

Question 13

What enzyme catalyses glycolysis to leave a low energy state?

Answer 13

Phosphofructokinase.

Question 14

Is phosphofructokinase activated by AMP or ATP?

Answer 14

AMP.

Question 15

Are glucose transporters always at the membrane or stored in vesicles?

Answer 15

Vesicles.

Question 16

Phosphofructokinase has a _______ feedback loop - one of its products, fructose-2,6-bisphosphate, _________ enhances phosphofructokinase.

Answer 16

Positive, allosterically.

Question 17

Which one inhibits phosphofructokinase - ADP or ATP?

Answer 17

ATP.

Question 18

Is glucokinase only found in liver cells?

Answer 18

Yes.

Question 19

What is the end product of hexokinase and glucokinase?

Answer 19

Glucose-6-phosphate.

Question 20

Glucokinase has ____ affinity for glucose so that it only traps excess to store as glycogen.

Answer 20

Low.

Question 21

In aerobic cells with mitochondria, how is NAD+ regenerated?

Answer 21

Oxidative phosphorylation.

Question 22

In anaerobic yeast, what is NAD+ regeneration coupled to?

Answer 22

Ethanol and CO2 production.

Question 23

In anaerobic skeletal muscle, what is NAD+ regeneration coupled to?

Answer 23

Lactate production.

Question 24

What is the term for the recycling of lactate to glucose in the liver during exercise?

Answer 24

Gluconeogenesis.

Question 25

Pyruvate decarboxylation is the first step of which aerobic cycle?

Answer 25

TCA cycle.

Question 26

Is pyruvate converted into acetyl-CoA in aerobic or anaerobic mitochondrial cells?

Answer 26

Aerobic.

Question 27

As the first step of the investment phase of glycolysis, what does hexokinase do?

Answer 27

Phosphorylates glucose to trap it in the cell.

Question 28

What is the result of the preparatory phase of glycolysis?

Answer 28

Two identical cleavage products.

Question 29

What is the goal of the payoff phase of glycolysis?

Answer 29

Conversion of the cleavage products into pyruvate.

Question 30

Approximately what percentage of glucose energy is released by glycolysis?

Answer 30

5%.

Question 31

Can other sugars enter glycolysis?

Answer 31

Yes, but glucose is preferred.