METABOLISM OF GLYCOGEN

Question 1

A branched polysaccharide of glucose units.

Answer 1

Glycogen

Question 2

Where is glycogen stored?

Answer 2

Liver and muscle cells

Question 3

Function of glycogen

Answer 3

Energy reserve and glucose buffer

Question 4

What initiates glycogen synthesis

Answer 4

Glucose uptake and phosphorylation

Question 5

Key enzyme in glycogen synthesis

Answer 5

Glycogen synthase

Question 6

What regulates glycogen synthesis

Answer 6

Insulin, glucose, and ATP.

Question 7

Key enzyme in glycogen breakdown?

Answer 7

Glycogen phosphorylase.

Question 7

Initiates glycogen breakdown

Answer 7

Hormonal signals (e.g., glucagon, epinephrine).

Question 8

What regulates glycogen breakdown

Answer 8

Glucagon, epinephrine, and Ca2+.

Question 9

What regulates glycogen metabolism?

Answer 9

Hormonal regulation, allosteric control, and phosphorylation/dephosphorylation

Question 10

Role of insulin in glycogen metabolism?

Answer 10

Stimulates glycogen synthesis

Question 11

Role of glucagon in glycogen metabolism?

Answer 11

Stimulates glycogen breakdown

Question 12

What is von Gierke’s disease?

Answer 12

A glycogen storage disease characterized by impaired glycogen breakdown.

Question 13

How does diabetes mellitus affect glycogen metabolism?

Answer 13

Impairs glycogen synthesis.

Question 14

Consequence of excessive glycogen breakdown

Answer 14

Hypoglycemia

Question 15

Difference between glycogen and starch?

Answer 15

Glycogen is a branched polysaccharide, while starch is a linear polysaccharide.

Question 16

Role of glycogenin in glycogen synthesis?

Answer 16

Initiates glycogen synthesis by forming a protein-glycogen complex

Question 17

Effect of exercise on glycogen metabolism?

Answer 17

Stimulates glycogen breakdown in muscle cells.

Question 18

What regulates glycogen breakdown?
a) Insulin
b) Glucagon
c) Epinephrine
d) All of the above

Answer 18

d) All of the above

Question 19

Function of glycogen synthase?
A: Catalyzes the addition of glucose units to glycogen.

Answer 19

Catalyzes the addition of glucose units to glycogen.

Question 20

What is the function of glycogen phosphorylase?

Answer 20

A: Catalyzes the breakdown of glycogen to glucose-1-phosphate.

Question 20

How does insulin stimulate glycogen synthesis?

Answer 20

Activates glycogen synthase and inhibits glycogen phosphorylase.

Question 21

hat is the role of debranching enzyme in glycogen breakdown?

Answer 21

Removes branches in glycogen, allowing continued breakdown.

Question 21

How does glucagon stimulate glycogen breakdown?

Answer 21

Activates glycogen phosphorylase and inhibits glycogen synthase.

Question 22

How does ATP regulate glycogen metabolism?

Answer 22

Inhibits glycogen breakdown and stimulates glycogen synthesis.

Question 23

How does epinephrine regulate glycogen metabolism?

Answer 23

Stimulates glycogen breakdown and inhibits glycogen synthesis.

Question 24

What is the role of Ca2+ in glycogen metabolism?

Answer 24

Activates glycogen phosphorylase and stimulates glycogen breakdown.

Question 25

Glycogen storage disease type I, characterized by impaired glycogen breakdown.

Answer 25

von Gierke's disease

Question 26

Glycogen storage disease type II, characterized by impaired lysosomal glycogen breakdown

Answer 26

Pompe's disease

Question 27

Glycogen storage disease type III, characterized by impaired glycogen debranching.

Answer 27

Cori's disease

Question 28

first step in glycogen synthesis

Answer 28

Glucose uptake and phosphorylation.

Question 29

energy source for glycogen synthesis

Answer 29

ATP and UTP.

Question 30

What is the substrate for glycogen synthase?

Answer 30

UDP-glucose.

Question 31

enzyme catalyzes glycogen branching?

Answer 31

Glycogen branching enzyme.

Question 32

What enzyme catalyzes glycogen debranching?

Answer 32

Debranching enzyme

Question 33

Group of inherited disorders characterized by deficient mobilization of glycogen or deposition of abnormal forms of glycogen

Answer 33

Glycogen Storage Disease

Question 34

Integrates the regulation of glycogenolysis and glycogenesis by promoting simultaneous activation of phosphorylase and inhibition of glycogen synthase

Answer 34

Cyclic AMP

Question 35

Glucagon acts on heart muscle but not on

Answer 35

skeletal muscle

Question 36

A non-neuronal cells that stores glycogen in the brain

Answer 36

astrocytes

Question 37

Branching involves detachment of existing?/

Answer 37

Glycogen chains

Question 38

It synchronizes the activation of Glycogen Phosphorylase w/muscle contraction

Answer 38

Ca2+

Question 39

Vasopressin, oxytocin and angiotensin II activates the

Answer 39

cAMP-independent glycogenolysis

Question 40

This enzyme inactivates the glycogen phosphorylase

Answer 40

Protein Phosphate-1