Deck 25: Glycogen Synthesis

Question 1

The complete oxidation of a glucose residue from glycogen produces ________________ ATP.

Answer 1

31

Question 2

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
Glycogen _______________ is inhibited by phosphorylase kinase.

Answer 2

c

Question 3

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
__________________ acts as a "high-energy handle" for biosynthetic reactions, including glygogen synthesis.

Answer 3

UDP

Question 4

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
__________________ is is a primer that polymerizes the first few glucose molecules.

Question 5

In general, phospho- forms of glycogen synthase lead to ________________ levels of glycogen.

Question 6

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
The protein _______________ serves as the primer used by glycogen synthase.

Question 7

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
_______________ is the glycogen storage disease in which the defective enzyme is glucose 6-phosphatase.

Question 8

Insulin stimulates glycogen synthase by inactivating __________________.

Question 9

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
_______________ dissociates from phosphorylase a in the T state.

Question 10

Glycogen synthase catalyzes the transfer of a glucose residue from UDP-glucose to one of the __________________ ends of glycogen.

Question 11

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
_______________ is the activated form of glucose that is required for glycogen synthesis.

Question 12

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
The reaction catalyzed by __________________ transfers UDP-glucose to the hydroxyl of an existing glycogen core.

Question 13

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
Synthesis of glycogen starts with the phosphate group transfer from UTP to _______________.

Question 14

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
Hydrolysis of _______________ drives the formation of UDP-glucose.

Question 15

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
Glucosyl units are added to the _______________ end, or terminal, of glycogen.

Question 16

The glycogen branching enzyme moves a block of __________________ (or so) glucose residues to from a branch point at least four residues from a preexisting branch.

Question 17

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
_______________ is the storage disease in which light exercise results in cramps.

Question 18

Glycogen synthase is converted into the active form by the action of __________________.

Question 19

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) UDP-glucose
b) nonreducing
c) synthesis
d) glucose
e) glycogenin
f) Von Gierke disease
g) glycogen synthase
h) UTP-glucose
i) protein phosphatase 1 (PP1)
j) PPi
k) glycogen phosphate
l) McArdle disease
_______________ is the key regulatory enzyme in glycogen synthesis.

Question 20

There is a high __________________-to-insulin ratio in diabetes.

Question 21

How are new glucosyl units added to a growing glycogen molecule?

Question 22

Which is the true glucose-level sensor in the cell?

A) insulin
B) phosphorylase a
C) glucagon
D) glycogen synthase
E) protein phosphatase 1

Question 23

The __________________ creates a 1,6-glycosidic bond.

A) branching enzyme
B) glucose transferase
C) glycogen isomerase
D) glycogen synthase
E) None of the above.

Question 24

Which enzyme(s) is/are required to synthesize ɑ-1,4-glycosidic bonds in glycogen?

A) glycogen synthase
B) UDP-glucose phosphorylase
C) branching enzyme
D) A and B
E) B and C

Question 25

Glycogenin:

A) consists of dimmer proteins.
B) self-assembles eight glycosyl units.
C) is the primer for glycogen synthase.
D) B and C.
E) All of the above.

Question 26

______________ results from a loss or inactivation of insulin receptors.

A) Hypoglycemia
B) Hyperinsulinemia
C) Type I diabetes
D) Type II diabetes
E) None of the above.

Question 27

There is rare disease in which a critical serine in muscle glycogenin is mutated to alanine, which results in what biochemical outcome?

Question 28

An incorrect, tight binding of PP1 to glycogen synthase would result in:

A) a hyperactive glycogen synthase.
B) hyper-glycogen levels.
C) increased insulin action.
D) high blood glucose.
E) activated glycogen synthase.

Question 29

Explain how the liver responds to muscle challenges in insulin-dependent diabetes.

Question 30

Explain why Type I diabetes is often called "fasting in the sea of plenty."

Question 31

Explain the conversion between both a and b, and R and T forms of phosphorylase.

Question 32

The activated glucose donor of glycogen synthesis is:

A) glucose 1-phosphate.
B) glucose.
C) ATP.
D) UTP.
E) None of the above.

Question 33

Insulin binds to its receptor and causes what protein to be activated in the cytoplasm?

Question 34

The enzyme that begins the kinase cascade, activating glycogen degradation, is:

A) glycogen synthase.
B) phosphorylase kinase.
C) PKC.
D) PKA.
E) tyrosine kinase.

Question 35

Which of the following occur after a carbohydrate-rich meal?

A) Blood-glucose levels increase, leading to glycogen storage in the liver.
B) Blood-glucose levels increase, leading to glycogen storage in the muscle.
C) Glycogen storage in the muscle shuts down.
D) All of the above.
E) None of the above.

Question 36

At the center of a glycogen molecule is:

A) glucose.
B) glycogenin.
C) UDP-glucose.
D) glycogen synthase.
E) glycogen phosphorylase.

Question 37

Using thermodynamic terms, describe the mechanism by which UDP-glucose is formed.

Question 38

Type I diabetes leads to ______________ in the liver.

A) increased glucose transport
B) increased glycogen synthesis
C) a decrease in fructose 2,6-phosphate
D) a decrease in gluconeogenesis
E) All of the above.

Question 39

After exercise, muscle cell glycogen metabolism is regulated by:

A) insulin.
B) phosphorylase a.
C) glucagon.
D) glycogen synthase.
E) protein phosphatase 1.

Question 40

Explain why patients with McArdle disease do not accumulate lactate during light exercise.

Question 41

What did Carl and Gerti Cori discover about the cause of von Gierke disease? Briefly explain how this information helps to explain the symptoms of the disease.

Question 42

How does insulin stimulate glycogen synthesis?

Question 43

Explain how the formation of UDP-glucose from glucose 1-phosphate and UTP is essentially reversible.

Question 44

Give the reaction catalyzed by UDP-glucose pyrophosphorylase.