Question 1

What is the normal glucose concentration in blood?

Accepted Answer

A)   80-120 g/100 mL (4.4-6.7 M) 
B)   8-12 g/100 mL (0.44-0.67 M) 
C)   80-120 mg/100 mL (4.4-6.7 mM) 
D)   80-120  μ\muμ g/100 mL (4.4-6.7   μ\muμ M) 
E)   None of the answers is correct. F) A) and D)
G) B) and D)

Question 2

What protein is the  δ\deltaδ  subunit of phosphorylase kinase?

Accepted Answer

A)   protein kinase A
B)   phosphorylase
C)   adenylate cyclase
D)   protein phosphatase 1
E)   calmodulin F) C) and E)
G) None of the above

Question 3

Thermodynamically,the reaction glucose-1-phosphate + UTP  UDP-glucose + PPiis readily reversible.Explain why the formation of UDP-glucose from glucose-1-phosphate and UTP is essentially irreversible.

Accepted Answer

The hydrolysis of pyrophosphate (PP_i)to t...

Question 4

What hormone signifies the starved state?

Accepted Answer

A)   insulin
B)   glucagon
C)   epinephrine
D)   cortisol
E)   None of the answers is correct.F) B) and E)
G) B) and D)

Question 5

Which of the following serves as the glucose "sensor" enzyme in liver cells?

Accepted Answer

A)   glucose-6-phosphatase
B)   hexokinase
C)   phosphoglucomutase
D)   UDP-glucose pyrophosphorylase
E)   phosphorylase aF) A) and D)
G) D) and E)

Question 6

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

Accepted Answer

The answer of Glycogen synthase catalyzes the transfer of a...

Question 7

What are the fates of the glucose-1-phosphate derived from glycogen?

Accepted Answer

It is 1)converted into glucose-6-phospha...

Question 8

Why is the T state of glycogen phosphorylase less active?

Accepted Answer

A)   The adjacent amino acids are not phosphorylated, and thus the catalysis cannot be carried out.
B)   The active site is partially blocked.
C)   ATP cannot be bound by the T state.
D)   Glucose-1-phosphate remains bound to the active site.
E)   None of the answers is correct.F) A) and D)
G) C) and D)

Question 9

What is the activated form of glucose required for glycogen synthesis?

Accepted Answer

A)   glucose-6-phosphate
B)   glucose-1-phosphate
C)   ADP-glucose
D)   UDP-glucose
E)   GDP-glucoseF) A) and D)
G) B) and E)

Question 10

What is the function of liver glycogen degradation?

Accepted Answer

A)   For glucose export to other tissues when glucose levels are low
B)   To maintain glucose levels after a large meal
C)   To provide for the large energy needs of the liver
D)   To allow for synthesis of lipids
E)   None of the answers is correct.F) A) and C)
G) A) and B)

Question 11

What reaction cleaves a bond by the addition of orthophosphate?

Accepted Answer

A)   phosphorolysis
B)   phosphatase
C)   transphosphorylation
D)   oxidative phosphorylation
E)   None of the answers is correct.F) None of the above
G) A) and D)

Question 12

Insulin stimulates glycogen synthase by inactivating ________________________.

Accepted Answer

glycogen s...

Question 13

What liver enzyme catalyzes the hydrolysis of a phosphate group to produce glucose?

Accepted Answer

A)   glucose phosphorylase
B)   glucose-1-phosphatase
C)   glucose-4-phosphatase
D)   glucose-6-phosphatase
E)   None of the answers is correct.F) A) and C)
G) B) and D)

Question 14

Phosphorylase kinase becomes fully active by being phosphorylated and binding ___________.

Accepted Answer

The answer of Phosphorylase kinase becomes fully active by being...

Question 15

What is the primary glycosidic bond found in glycogen?

Accepted Answer

A)    α\alphaα -1,3
B)    α\alphaα -1,4
C)    α\alphaα -1,6
D)    β\betaβ -1,4
E)    β\betaβ -1,6 F) A) and D)
G) B) and D)

Question 16

Why can't the glucose 1-phosphate diffuse out of the cell?

Accepted Answer

There is no membrane transport...

Question 17

In skeletal muscle,the binding of ___________ converts phosphorylase b into the active form.

Accepted Answer

The answer of In skeletal muscle,the binding of ___________ converts...

Question 18

Draw a structure showing the most common linkage between glucose units found in glycogen.

Accepted Answer

The structure should...

Question 19

What path in addition to the cAMP-induced signal transduction is used in the liver to stimulate glycogen breakdown by epinephrine?

Accepted Answer

In the liver,epinephrine also binds to a...

Question 20

What type of glycosidic bond is found at the branch points of glycogen?

Accepted Answer

A)    α\alphaα -1,2
B)    α\alphaα -1,4
C)    α\alphaα -1,6
D)    β\betaβ -1,4
E)    β\betaβ -1,6 F) B) and D)
G) A) and D)

Exam 21: Glycogen Metabolism

What type of glycosidic bond is found at the branch points of glycogen?

Correct AnswerverifiedShow Answer

What liver enzyme catalyzes the hydrolysis of a phosphate group to produce glucose?

Correct AnswerverifiedShow Answer

Thermodynamically,the reaction glucose-1-phosphate + UTP UDP-glucose + PPiis readily reversible.Explain why the formation of UDP-glucose from glucose-1-phosphate and UTP is essentially irreversible.

Correct AnswerverifiedThe hydrolysis of pyrophosphate (PPi)to t...View AnswerShow Answer

What path in addition to the cAMP-induced signal transduction is used in the liver to stimulate glycogen breakdown by epinephrine?

Correct AnswerverifiedIn the liver,epinephrine also binds to a...View AnswerShow Answer

What are the fates of the glucose-1-phosphate derived from glycogen?

Correct AnswerverifiedIt is 1)converted into glucose-6-phospha...View AnswerShow Answer

Phosphorylase kinase becomes fully active by being phosphorylated and binding ___________.

Correct AnswerverifiedShow Answer

In skeletal muscle,the binding of ___________ converts phosphorylase b into the active form.

Correct AnswerverifiedShow Answer

What is the function of liver glycogen degradation?

Correct AnswerverifiedShow Answer

What reaction cleaves a bond by the addition of orthophosphate?

Correct AnswerverifiedShow Answer

What protein is the δ\deltaδ subunit of phosphorylase kinase?

Correct AnswerverifiedShow Answer

Which of the following serves as the glucose "sensor" enzyme in liver cells?

Correct AnswerverifiedShow Answer

What hormone signifies the starved state?

Correct AnswerverifiedShow Answer

Insulin stimulates glycogen synthase by inactivating ________________________.

Correct Answerverifiedglycogen s...View AnswerShow Answer

What is the primary glycosidic bond found in glycogen?

Correct AnswerverifiedShow Answer

Why can't the glucose 1-phosphate diffuse out of the cell?

Correct AnswerverifiedThere is no membrane transport...View AnswerShow Answer

Draw a structure showing the most common linkage between glucose units found in glycogen.

Correct AnswerverifiedThe structure should...View AnswerShow Answer

Why is the T state of glycogen phosphorylase less active?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

What is the normal glucose concentration in blood?

Correct AnswerverifiedShow Answer

What is the activated form of glucose required for glycogen synthesis?

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Thermodynamically,the reaction glucose-1-phosphate + UTP UDP-glucose + PP_iis readily reversible.Explain why the formation of UDP-glucose from glucose-1-phosphate and UTP is essentially irreversible.

Correct Answer
verified
The hydrolysis of pyrophosphate (PP_i)to t...
View Answer

Correct Answer
verified
In the liver,epinephrine also binds to a...
View Answer

Correct Answer
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It is 1)converted into glucose-6-phospha...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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What protein is the $\delta$ subunit of phosphorylase kinase?

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Correct Answer
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Correct Answer
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Correct Answer
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glycogen s...
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Correct Answer
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Correct Answer
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There is no membrane transport...
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The structure should...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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