Question 1

Which of the following amino acid breakdown reactions would be catalyzed by an aminotransferase?

Accepted Answer

A)  Threonine  →\rarr→  Acetyl CoA
B)  Alanine  →\rarr→  Pyruvate
C)  Asparagine  →\rarr→  Aspartate
D)  Homocysteine  →\rarr→  Methionone
E)  HMG-CoA  →\rarr→  Acetoacetate

Question 2

A mutation in GDH of patients with HI/HA (hypoglycemia/hyperammonemia) results in a decrease in allosteric control of GDH via GTP.Which of the following will be observed in the patients?

Accepted Answer

A)  an increase in ammonia
B)  an increase in glutamate
C)  an increase in NADH
D)  A and B
E)  A and C

Question 3

Which of the following amino acids is NOT synthesized from aspartate?

Accepted Answer

A)  threonine
B)  methionine
C)  lysine
D)  cysteine
E)  All of the above are synthesized from aspartic acid.

Question 4

Which of the following require a cyclic carbohydrate precursor for synthesis?
I.histidine
II.alanine
III.arginine
IV.tyrosine

Accepted Answer

A)  I, II
B)  II only
C)  I, III
D)  I , IV
E)  II, IV

Question 5

The lifetime of a protein in cells actively involved in metabolism

Accepted Answer

A)  is longer in eukaryotes than in prokaryotes.
B)  ranges from months to years.
C)  is independent of the function and activity of the protein.
D)  can change in response to changes in metabolic hormone levels.
E)  none of the above

Question 6

Which of the following is(are) advantages to the constant degradation and reformation of proteins?

Accepted Answer

A)  Nutrients can be stored as proteins, which can be used during periods of metabolic need.
B)  Damaged proteins are eliminated so they do not accumulate.
C)  Metabolism can be efficiently regulated by the synthesis and degradation of enzymes.
D)  All of the above are advantages.
E)  None of the above is an advantage.

Question 7

In which cellular location listed below does the following reaction take place? 
ornithine + carbamoyl-phosphate → citrulline

Accepted Answer

A)  cytosol
B)  mitochondrial matrix
C)  lysosome
D)  A or B
E)  none of the above

Question 8

Which of the following describes the steps required prior to ATP-dependent degradation of proteins?
I.Ubiquitin is transferred to cysteine on a ubiquitin-conjugating enzyme.
II.The protein is linked to at least four tandemly linked ubiquitin units.
III.Activated ubiquitin is transferred to a lysine of the previously bound protein.
IV.Ubiquitin is attached via a thioester to a unbiquitin-activiating enzyme.

Accepted Answer

A)  I, II, III, IV
B)  IV, I, III, II
C)  II, I, III, IV
D)  IV, II, I, III
E)  IV, II, III, I

Question 9

Which of the following reaction sequences could result in glucose synthesis?

Accepted Answer

A)  fumarate  →\rarr→  arginine  →\rarr→  urea
B)  fumarate  →\rarr→  malate  →\rarr→  oxaloacetate
C)  citrulline  →\rarr→  urea  →\rarr→ aspartate
D)  urea  →\rarr→  arginine  →\rarr→  ornithine
E)  none of the above

Question 10

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Organisms known as _____ can fix nitrogen into metabolically useful molecules.

Accepted Answer

A)  ribosomes
B)  jaundice
C)  channeling
D)  26S proteasome
E)  glutamine synthetaseF) alanineG) glutamateH) vitamin B6I) anammoxJ) glutamine transferaseK) THFL) autotrophM) vitamin DN) lysosomesO) diazotrophs

Question 11

Which of the following statements about maple syrup urine disease is FALSE?
I.It is caused by a genetic deficiency in the enzyme BCKDH.
II.The disease is fatal unless promptly treated.
III.There is a buildup of the branched-chain  α\alphaα -keto acids.
IV.Patients with the disease excrete urine that smells like maple syrup.

Accepted Answer

A)  I only
B)  II only
C)  I, III
D)  III, IV
E)  All of the statements are true.

Question 12

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-A phenomenon in which intermediates are directly transferred from one active site to another is ______.

Accepted Answer

A)  ribosomes
B)  jaundice
C)  channeling
D)  26S proteasome
E)  glutamine synthetaseF) alanineG) glutamateH) vitamin B6I) anammoxJ) glutamine transferaseK) THFL) autotrophM) vitamin DN) lysosomesO) diazotrophs

Question 13

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-The amino acid ______ has been thought to act as a transfer system for NH3, safely allowing the toxic molecule to be transported from the liver to the kidneys.

Accepted Answer

A)  ribosomes
B)  jaundice
C)  channeling
D)  26S proteasome
E)  glutamine synthetaseF) alanineG) glutamateH) vitamin B6I) anammoxJ) glutamine transferaseK) THFL) autotrophM) vitamin DN) lysosomesO) diazotrophs

Question 14

What species are combined to produce carbamoyl phosphate?

Accepted Answer

A)  NH3 , PO43−, HCO3−
B)  NH4+, PO43−, Ac-CoA, releasing CoA-SH
C)  glycine & inorganic phosphate, releasing CO2
D)  acetate & NH4+, releasing CO2
E)  alanine & inorganic phosphate, releasing acetate

Question 15

The total cost of nitrogen reduction is ____ and ___ transferred electrons.

Accepted Answer

A)  8 ATP; 4
B)  12 ATP; 8
C)  12 ATP; 6
D)  16 ATP; 8
E)  16 ATP; 6

Question 16

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-Infants who cannot properly degrade bilirubin develop ______.

Accepted Answer

A)  ribosomes
B)  jaundice
C)  channeling
D)  26S proteasome
E)  glutamine synthetaseF) alanineG) glutamateH) vitamin B6I) anammoxJ) glutamine transferaseK) THFL) autotrophM) vitamin DN) lysosomesO) diazotrophs

Question 17

The pictured compound, glutamate-5-semialdehyde, is an intermediate in the biosynthesis of which of the following amino acids?

Accepted Answer

A)  histidine
B)  arginine
C)  methionine
D)  threonine
E)  More than one of the above is made from this intermediate.

Question 18

The presence of SGOT and SGPT in the serum indicate potential

Accepted Answer

A)  starvation and brain tissue damage.
B)  inflammation.
C)  heart attack or liver damage.
D)  lung or breast cancer.
E)  none of the above

Question 19

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-The enzyme ______ is critical to regulating nitrogen metabolism.

Accepted Answer

A)  ribosomes
B)  jaundice
C)  channeling
D)  26S proteasome
E)  glutamine synthetaseF) alanineG) glutamateH) vitamin B6I) anammoxJ) glutamine transferaseK) THFL) autotrophM) vitamin DN) lysosomesO) diazotrophs

Question 20

Which of the following are essential amino acids for adult humans?

Accepted Answer

A)  Arg, His, Gly, Try
B)  Met, Lys, His, Val
C)  His, Leu, Tyr, Ala
D)  Met, Gly, Thr, Ser
E)  Ala, Arg, Cys, Ser

Exam 21: Amino Acid Metabolism

The total cost of nitrogen reduction is __ and _ transferred electrons.

Correct Answer
verified

Which of the following reaction sequences could result in glucose synthesis?

Correct Answer
verified

Which of the following require a cyclic carbohydrate precursor for synthesis? I.histidine II.alanine III.arginine IV.tyrosine

Correct Answer
verified

Matching Choose the correct answer from the list. Not all the answers will be used. -A phenomenon in which intermediates are directly transferred from one active site to another is ______.

Correct Answer
verified

Which of the following is(are) advantages to the constant degradation and reformation of proteins?

Correct Answer
verified

The presence of SGOT and SGPT in the serum indicate potential

Correct Answer
verified

Matching Choose the correct answer from the list. Not all the answers will be used. -Infants who cannot properly degrade bilirubin develop ______.

Correct Answer
verified

Which of the following are essential amino acids for adult humans?

Correct Answer
verified

Which of the following amino acid breakdown reactions would be catalyzed by an aminotransferase?

Correct Answer
verified

Matching Choose the correct answer from the list. Not all the answers will be used. -Organisms known as _____ can fix nitrogen into metabolically useful molecules.

Correct Answer
verified

In which cellular location listed below does the following reaction take place? ornithine + carbamoyl-phosphate → citrulline

Correct Answer
verified

What species are combined to produce carbamoyl phosphate?

Correct Answer
verified

Matching Choose the correct answer from the list. Not all the answers will be used. -The enzyme ______ is critical to regulating nitrogen metabolism.

Correct Answer
verified

Which of the following amino acids is NOT synthesized from aspartate?

Correct Answer
verified

A mutation in GDH of patients with HI/HA (hypoglycemia/hyperammonemia) results in a decrease in allosteric control of GDH via GTP.Which of the following will be observed in the patients?

Correct Answer
verified

The lifetime of a protein in cells actively involved in metabolism

Correct Answer
verified

Matching Choose the correct answer from the list. Not all the answers will be used. -The amino acid ______ has been thought to act as a transfer system for NH₃, safely allowing the toxic molecule to be transported from the liver to the kidneys.

Correct Answer
verified

The pictured compound, glutamate-5-semialdehyde, is an intermediate in the biosynthesis of which of the following amino acids?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Exam 21: Amino Acid Metabolism

The total cost of nitrogen reduction is ____ and ___ transferred electrons.

Correct AnswerverifiedShow Answer

Which of the following reaction sequences could result in glucose synthesis?

Correct AnswerverifiedShow Answer

Which of the following require a cyclic carbohydrate precursor for synthesis? I.histidine II.alanine III.arginine IV.tyrosine

Correct AnswerverifiedShow Answer

Matching Choose the correct answer from the list. Not all the answers will be used. -A phenomenon in which intermediates are directly transferred from one active site to another is ______.

Correct AnswerverifiedShow Answer

Which of the following is(are) advantages to the constant degradation and reformation of proteins?

Correct AnswerverifiedShow Answer

The presence of SGOT and SGPT in the serum indicate potential

Correct AnswerverifiedShow Answer

Matching Choose the correct answer from the list. Not all the answers will be used. -Infants who cannot properly degrade bilirubin develop ______.

Correct AnswerverifiedShow Answer

Which of the following are essential amino acids for adult humans?

Correct AnswerverifiedShow Answer

Which of the following amino acid breakdown reactions would be catalyzed by an aminotransferase?

Correct AnswerverifiedShow Answer

Matching Choose the correct answer from the list. Not all the answers will be used. -Organisms known as _____ can fix nitrogen into metabolically useful molecules.

Correct AnswerverifiedShow Answer

In which cellular location listed below does the following reaction take place? ornithine + carbamoyl-phosphate → citrulline

Correct AnswerverifiedShow Answer

What species are combined to produce carbamoyl phosphate?

Correct AnswerverifiedShow Answer

Matching Choose the correct answer from the list. Not all the answers will be used. -The enzyme ______ is critical to regulating nitrogen metabolism.

Correct AnswerverifiedShow Answer

Which of the following amino acids is NOT synthesized from aspartate?

Correct AnswerverifiedShow Answer

A mutation in GDH of patients with HI/HA (hypoglycemia/hyperammonemia) results in a decrease in allosteric control of GDH via GTP.Which of the following will be observed in the patients?

Correct AnswerverifiedShow Answer

The lifetime of a protein in cells actively involved in metabolism

Correct AnswerverifiedShow Answer

Matching Choose the correct answer from the list. Not all the answers will be used. -The amino acid ______ has been thought to act as a transfer system for NH3, safely allowing the toxic molecule to be transported from the liver to the kidneys.

Correct AnswerverifiedShow Answer

The pictured compound, glutamate-5-semialdehyde, is an intermediate in the biosynthesis of which of the following amino acids?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The total cost of nitrogen reduction is __ and _ transferred electrons.

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Matching Choose the correct answer from the list. Not all the answers will be used. -The amino acid ______ has been thought to act as a transfer system for NH₃, safely allowing the toxic molecule to be transported from the liver to the kidneys.

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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