$$\text{fructose-6-phosphate} + \text{ATP} \rightarrow \text{fructose-2,6-bisphosphate} + \text{ADP}$$

$$\text{UDP-glucose} + \text{glycogen}_{n} \rightarrow \text{glycogen}_{n+1} + \text{UDP}$$

Question 1

Which molecule is considered the most sensitive indicator of the energetic status of a cell?

Accepted Answer

AMP

Question 2

Glycogen phosphorylase catalyzes which of the following reactions?

Accepted Answer

Cleavage of $$	ext{α}-1$$,4 bonds

Question 3

Which enzyme is responsible for removing branches in glycogen during glycogenolysis?

Accepted Answer

Glucose-1-phosphate debranching enzyme

Question 4

Oxygen branching enzyme catalyzes the formation of which type of bond in glycogen?

Accepted Answer

$$	ext{α}-1$$,6 bonds

Question 5

Which of the following statements about glycogen is TRUE?

Accepted Answer

Insulin stimulates glycogen synthesis.

Question 6

Glycogen synthase can be allosterically inhibited by which molecule?

Accepted Answer

AMP

Question 7

Phosphofructokinase-2 is inhibited by which molecule?

Accepted Answer

ATP

Question 8

Which of the following reactions is catalyzed by phosphofructokinase-2?

Accepted Answer

$$	ext{fructose-6-phosphate} + 	ext{ATP} ightarrow 	ext{fructose-2,6-bisphosphate} + 	ext{ADP}$$

Question 9

Which hormone stimulates glycogen breakdown in the liver?

Accepted Answer

Glucagon

Question 10

A patient with a deficiency in the glycogen branching enzyme would most likely have abnormal glycogen with which characteristic?

Accepted Answer

Long, unbranched chains

Question 11

Which of the following best describes the role of AMP in the regulation of glycogen metabolism?

Accepted Answer

AMP activates glycogen phosphorylase.

Question 12

During fasting, which enzyme is most likely to be activated in the liver to maintain blood glucose levels?

Accepted Answer

Glycogen phosphorylase

Question 13

Which of the following is a direct product of the reaction catalyzed by glycogen phosphorylase?

Accepted Answer

Glucose-1-phosphate

Question 14

Which enzyme is responsible for converting glucose-1-phosphate to glucose-6-phosphate during glycogenolysis?

Accepted Answer

Phosphoglucomutase

Question 15

Which of the following best explains why ATP inhibits phosphofructokinase-2?

Accepted Answer

High ATP levels signal sufficient energy, reducing glycolysis.

Question 16

A mutation that increases the activity of glycogen synthase would most likely result in which clinical outcome?

Accepted Answer

Increased glycogen storage

Question 17

Which of the following is NOT a function of insulin in glucose metabolism?

Accepted Answer

Stimulates gluconeogenesis

Question 18

Which of the following reactions is catalyzed by glycogen synthase?

Accepted Answer

$$	ext{UDP-glucose} + 	ext{glycogen}_{n} ightarrow 	ext{glycogen}_{n+1} + 	ext{UDP}$$

Question 19

Which of the following would most likely occur if phosphofructokinase-2 is inhibited?

Accepted Answer

Decreased fructose-2,6-bisphosphate levels

Question 20

Which of the following best describes the effect of glucagon on liver cells?

Accepted Answer

Activates glycogen phosphorylase

Glucose and Glycogen Regulation: Practice Questions and Explanations

Guida di studio - Domande di pratica