Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biochemistry II > TopHat Questions > Flashcards

TopHat Questions Flashcards

1
Q

Identify an enzyme in glycolysis that is a focal point for pathway regulation.

A

hexokinase
PFK-1
pyruvate kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which of the following tissues does NOT produce GLUT4?
A. Liver
B. Cardiac muscle
C. Adipose
D. Skeletal muscle
E. None of the above

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

An increase of insulin in the blood leads to which of the following?
A. Increased presence of GLUT4 in the cell membranes of adipocytes
B. Decreased expression of glucose-6-phosphatase
C. Increased expression of hexokinase IV in hepatocytes
D. Increased glucose uptake by cardiac muscle cells
E. All of the above
F. None of the above

A

E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Allosteric enzymes ____________.
A. Always have quaternary structure
B. Usually catalyze reactions with DG’s close to 0
C. Are regulated by way of protein conformational changes
D. Have no bearing on rates of metabolic processes
E. All of the above
F. None of the above

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

An allosteric inhibitor does which of the following?
A. Removes positive cooperativity
B. Enhances positive cooperativity
C. Binds preferentially to the relaxed (R) state
D. Competes directly with substrate for binding to the enzyme
E. None of the above

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Fructose-2,6-bisphosphate will _____________ the effect of phosphoenolpyruvate on PFK-1.
A. Enhance
B. Counteract
C. Neither A nor B

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Fructose-2,6-bisphosphate will _____________ the effect of AMP on FBPase-1.
A. Enhance
B. Counteract
C. Neither A nor B

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

In response to insulin, fructose-2,6-bisphosphate levels will ___________ in
hepatocytes and ____________ in cardiomyocytes
A. increase, decrease
B. decrease, remain unchanged
C. remain unchanged, increase
D. decrease, increase
E. increase, increase

A

E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

In response to epinephrine, fructose-2,6-bisphosphate levels will ___________ in
hepatocytes and ____________ in cardiomyocytes
A. increase, decrease
B. decrease, remain unchanged
C. remain unchanged, increase
D. decrease, increase
E. increase, remain unchanged

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Identify an enzyme whose activity is inhibited by acetyl-CoA in glycolysis

A

pyruvate kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which of the following does not occur in hepatocytes in response to insulin signaling?
A. Increased hexokinase IV expression
B. Pyruvate kinase phosphorylation
C. Increased fructose-2,6-bisphosphate production
D. Decreased PEPCK expression
E. None of the above

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which of the following occurs in hepatocytes in response to glucagon signaling?
A. Increased hexokinase IV expression
B. Increased fructose-2,6-bisphosphate production
C. Decreased PEPCK expression
D. Phosphorylation of PFK-2/FBPase-2
E. All of the above

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which of the following is NOT an enzyme used in glycogenolysis?
A. glycogen phosphorylase
B. UDP-glucose pyrophosphorylase
C. phosphoglucomutase
D. None of the above

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Liberation of a glucose from glycogen requires the expenditure of how many ATP?

A

0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Epinephrine signaling would be expected to ___________ glycogenesis in liver
cells and _____________ glycogenesis in skeletal muscle cells.
A. increase, increase
B. decrease, increase
C. increase, decrease
D. decrease, decrease

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which of the following hepatocyte enzymes is a substrate for protein kinase A?
A. Pyruvate kinase
B. PFK-2/FBPase-2
C. Glycogen synthase
D. Phosphorylase kinase
E. All of the above

A

E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The substrate for phosphodiesterase is ___________.
A. ATP
B. cAMP
C. Phosphoprotein phosphatase-1
D. Protein kinase A
E. All of the above

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Increased phosphodiesterase activity will result in___________ protein kinase A activity
A. increased
B. decreased
C. no change in

A

A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Put the following events in insulin signaling in the correct order.
A. IRS-1 phosphorylation
B. Insulin binds to the insulin receptor
C. PIP3 production
D. Protein kinase B phosphorylation
E. GLUT4 cell surface presentation
F. Receptor tyrosine kinase autophosphorylation

A

B – F – A – C – D – E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which of the following will occur within a hepatocyte in response to glucagon?
A. [cAMP] will decrease
B. [Fructose-2,6-bisphosphate] will decrease
C. PEPCK expression will decrease
D. Glycogen synthase will be dephosphorylated
E. All of the above

A

B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which of the following will occur within a hepatocyte in response to insulin?
A. [cAMP] will decrease
B. [Fructose-2,6-bisphosphate] will increase
C. PEPCK expression will decrease
D. Glycogen synthase will be dephosphorylated
E. All of the above

A

E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Metabolically speaking, pyruvate can be converted to which of the following?
A. oxaloacetate
B. alanine
C. acetyl-CoA
D. lactate
E. all of the above

A

E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the most abundant direct product of the citric acid cycle?

A

NADH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The pyruvate dehydrogenase complex is composed of how many subunits?

A

324

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which of the following is a cofactor used by isocitrate dehydrogenase?
A. FAD
B. Thiamine pyrophosphate
C. Lipoamide
D. All of the above
E. None of the above

A

E

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which of the following is a cofactor used by a-ketoglutarate dehydrogenase?
A. FAD
B. Thiamine pyrophosphate
C. Lipoamide
D. All of the above
E. None of the above

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Once pyruvate is converted to acetyl-CoA, which of the following is NOT a
possible fate for acetyl-CoA.
A. Gluconeogenesis
B. Oxidation through the citric acid cycle
C. Fatty acid synthesis
D. Cholesterol synthesis
E. None of the above

A

A

28
Q

Oxaloacetate is ___________________.
A. a substrate
B. a product
C. a catalyst
D. A and B
E. A, B, and C

A

E

29
Q

The P/O ratio for NADH is ___________________.

A

2.5 or 1.5

30
Q

Which of the following complexes is NOT involved in succinate oxidation by O2?
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
E. None of the above

A

A

31
Q

The P/O ratio for NADH generated in the cytosol is ___________________.
A. 1
B. 1.5
C. 2
D. 2.5
E. 3

A

B D

32
Q

Including the action of respiratory electron transport and the F1FOATPase, how
many ATPs will be generated as a result of converting one pyruvate to an acetylCoA?

A

2.5

33
Q

Almost all oxidoreductases require a cofactor(s) to function. T/F

A

true

34
Q

Exposure to rotenone will lead to an increase in lactate production. T/F?

A

true

35
Q

Which of the following molecules is an inhibitor of complex IV?
A. cyanide (CN-)
B. azide (N3-)
C. carbon monoxide (CO)
D. all of the above
E. none of the above

A

D

36
Q

Which of the following is expected to occur upon inhibition of complex IV?
A. Ubiquinol accumulation
B. NAD+ depletion
C. Lactate accumulation
D. All of the above

A

D

37
Q

I am an electron transport complex. I have no Rieske Fe/S centers, no hemes,
and no FAD. Who am I?
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
E. None of the above

A

A

38
Q

I am an electron transport complex. I have an Fe/S center and hemes, but I do
not have a flavin. Who am I?
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
E. None of the above

A

C

39
Q

Introduction of a K+ channel in the mitochondrial inner membrane would disrupt ATP
synthesis. T/F?

A

A

40
Q

Introduction of a K+ channel in the mitochondrial inner membrane would be expected
to result in lactate accumulation. T/F?

A

F

41
Q

Dicoumarol binds to which of the following complexes?
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
E. F1FO ATPase
F. None of the above

A

F

42
Q

The activity of which of the following complexes is inhibited because of dicoumarol?
A. Complex I
B. Complex II
C. Complex III
D. Complex IV
E. F1FO ATPase
F. None of the above

A

E

43
Q

Consider a eukaryotic organism whose F1FO ATPase contains 9 c subunits. Passage
of how many H+ across the mitochondrial inner membrane will result in one full
revolution of the ring of c subunits?

A

9

44
Q

Consider a eukaryotic organism whose F1FO ATPase contains 9 c subunits. Passage
of how many H+ across the mitochondrial inner membrane will result in one full
revolution of the g subunit?

A

9

45
Q

Considering a eukaryotic organism that uses the structures and mechanisms of
the respiratory electron transport complexes as discussed in class, an F1FO ATPase
with 9 c subunits, and ATP/ADP translocase, how many ATPs should be produced
and available for use as a result of the oxidation of two succinates to two
fumarates?

A

3

46
Q

Catalyzes the hydrolysis of triacylglycerol in chylomicrons.
A. Pancreatic lipase
B. Lipoprotein lipase
C. Triacylglycerol lipase
D. All of the above
E. None of the above

A

B

47
Q

Catalyzes the hydrolysis of triacylglycerol stored in adipose tissue.
A. Pancreatic lipase
B. Lipoprotein lipase
C. Triacylglycerol lipase
D. All of the above
E. None of the above

A

C

48
Q

Triacylglycerol lipase activity increases in response to glucagon signaling. T/F?

A

true

49
Q

The complete b-oxidation of a stearoyl-CoA will produce how many acetylCoA, FADH2, and NADH?
A. 9 acetyl-CoA, 9 FADH2, and 9 NADH
B. 18 acetyl-CoA, 9 FADH2, and 9 NADH
C. 9 acetyl-CoA, 8 FADH2, and 8 NADH
D. 8 acetyl-CoA, 7 FADH2, 7 NADH
E. 1 acetyl-CoA, 1 FADH2, 1 NADH

A

C

50
Q

Ketogenesis (synthesis of ketone bodies) occurs along with which of the
following?
A. Long-term fasting state
B. Elevated activity of TAG lipase
C. Increased rates of b-oxidation
D. All of the above
E. None of the above

A

D

51
Q

In mammals, the catabolism of stearate to CO2 will lead to the generation of
how many ATP?
A. 9
B. 32
C. 64
D. 106
E. 120

A

9

52
Q

Carnitine acyl transferase I is inhibited by __________.
A. ATP
B. malonyl-CoA
C. acetyl-CoA
D. glucose
E. all of the above

A

B

53
Q

Pyruvate dehydrogenase kinase _____________________.
A. is inhibited by pyruvate
B. is activated by NADH
C. is activated by acetyl-CoA
D. inactivates the pyruvate dehydrogenase complex
E. all of the above

A

E

54
Q

Glycerol kinase is expressed in which of the following cell types?
A. adipocytes
B. cardiomyocytes
C. intestinal epithelial cells (enterocytes)
D. hepatocytes
E. all of the above

A

D

55
Q

Glycerol kinase is expressed in which of the following cell types?
A. adipocytes
B. cardiomyocytes
C. intestinal epithelial cells (enterocytes)
D. hepatocytes
E. all of the above

A

D

56
Q

The direct carbon donor used by fatty acid synthase for each round of fatty acid
synthesis is acetyl-CoA. T/F?

A

false

57
Q

What enzyme is present only in hepatocytes that enables them to synthesize
ketone bodies (particularly acetoacetate)?
A. succinyl-CoA synthetase
B. HMG-CoA lyase
C. b-ketoacyl-CoA transferase
D. b-hydroxybutyrate dehydrogenase
E. None of the above

A

B

58
Q

What enzyme is absent in hepatocytes that would otherwise allow them to
catabolize b-hydroxybutyrate and/or acetoacetate?
A. succinyl-CoA synthetase
B. HMG-CoA lyase
C. b-ketoacyl-CoA transferase
D. b-hydroxybutyrate dehydrogenase
E. None of the above

A

C

59
Q

The cofactor used by acetyl-CoA carboxylase is _____________.
A. Thiamin pyrophosphate
B. NADP+
C. Biotin
D. 5’-deoxyadenosylcobalamin
E. Lipoic acid

A

C

60
Q

Insulin would be expected to __________ acetyl-CoA carboxylase activity in
hepatocytes.
A. increase
B. decrease
C. have no effect on

A

A

61
Q

Glucagon would be expected to __________ malonyl-CoA production in
hepatocytes.
A. increase
B. decrease
C. have no effect on

A

B

62
Q

Insulin would be expected to __________ carnitine acyl transferase I activity in
hepatocytes.
A. increase
B. decrease
C. have no effect on

A

B

63
Q

Which of the following redox cofactors is used by fatty acid synthase?
A. NADH
B. FADH2
C. NADPH
D. All of the above
E. None of the above

A

C

64
Q

For a fatty acid containing an even number of carbons (as is typical), all of the
carbon it contains is derived from acetyl-CoA. T/F?

A

true

65
Q

Fatty acid synthase almost always generates palmitate as a final product. Which
enzyme activity is primarily responsible for dictating the length of the fatty acid
produced?
A. the b-ketoacyl-ACP synthase
B. the acyl carrier protein
C. the b-ketoacyl-ACP reductase
D. the b-hydroxyacyl-ACP dehydratase
E. the thioesterase

A

E

66
Q

In mammals, all of the activities necessary for fatty acid synthesis are contained
on ______________ polypeptide(s).
A. one
B. two
C. three
D. four
E. seven

A

A

Biochemistry II (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions