Question 1

The amino acid __________ and is an intermediate in the biosynthesis of _________.

Accepted Answer

A)  histidine;purines
B)  glycine;heme
C)  serine;heme
D)  serine;sphingosine
E)  glutamine;glutathioneF) A) and B)
G) C) and E)

Question 2

Which of the following is not a chemotherapeutic drug?

Accepted Answer

A)  Azaserine
B)  Allopurinol
C)  Fluorouracil
D)  Methotrexate
E)  AcivicinF) A) and D)
G) B) and D)

Question 3

Bile pigments are:

Accepted Answer

A)  formed in the degradation of heme.
B)  generated by oxidation of sterols.
C)  responsible for light reception in the vertebrate eye.
D)  secreted from the pancreas
E)  the products of purine degradation.F) A) and E)
G) C) and D)

Question 4

Give the name and structure of the glycolytic or citric acid cycle intermediate that has the same carbon skeleton as (a)alanine, (b)glutamate, (c)aspartate.

Accepted Answer

(a)Pyruvate CH₃-CO-...

Question 5

Describe the pathway by which GMP is converted into GTP;show the co-substrates that are involved and name the enzymes.

Accepted Answer

GMP + ATP <img  loading="lazy" src="/assets/images/blured-textbook.svg" class="d-inline m-1" alt="blured image" width="139" height="30"> GDP + ADP (nucleosi...

Question 6

The most direct precursors of the nitrogens of UMP are:

Accepted Answer

A)  aspartate and carbamoyl phosphate.
B)  glutamate and aspartate.
C)  glutamate and carbamoyl phosphate.
D)  glutamine and aspartate.
E)  glutamine and carbamoyl phosphate.F) A) and B)
G) C) and D)

Question 7

CMP,UMP,and TMP all have ________________ as a common precursor.

Accepted Answer

A)  adenosine
B)  aspartate
C)  glutamine
D)  inosine
E)  S-adenosyl methionineF) None of the above
G) B) and C) B

Question 8

Draw the structure of 5'-GMP.Indicate with an arrow the atom(s)derived from glutamine's amide group(s).

Accepted Answer

The structure of 5'-GMP is sho...

Question 9

The hormones epinephrine and norepinephrine are derived biosynthetically from:

Accepted Answer

A)  arginine.
B)  histidine.
C)  isoleucine.
D)  tryptophan.
E)  tyrosine.F) A) and E)
G) C) and D)

Question 10

An amino acid that does not derive its carbon skeleton,at least in part,from oxaloacetate is:

Accepted Answer

A)  aspartate.
B)  lysine.
C)  methionine.
D)  proline.
E)  threonine.F) C) and E)
G) C) and D)

Question 11

Describe and contrast,with diagrams,concerted (cumulative)feedback regulation and sequential feedback inhibition.

Accepted Answer

Both are allosteric mechanisms to reduce...

Question 12

Erythrose 4-phosphate is a precursor of:

Accepted Answer

A)  aspartate.
B)  cysteine.
C)  phenylalanine.
D)  serine.
E)  threonine.F) D) and E)
G) B) and D)

Question 13

In which group are all the amino acids closely interrelated metabolically?

Accepted Answer

A)  Arginine,hydroxyproline,and histidine
B)  Arginine,tyrosine,and glutamate
C)  Glycine,valine,glutamine,and aspartate
D)  Ornithine,alanine,glycine,and valine
E)  Ornithine,proline,arginine,and glutamateF) A) and E)
G) B) and E) E

Question 14

Show the reaction catalyzed by glycine synthase,indicating the role of any cofactors that participate.

Accepted Answer

CO₂ + NH₄

Question 15

Trace the path of nitrogen from atmospheric N2 into glutamate.Name the intermediates (no structures necessary)and enzymes,and show any coenzymes involved.

Accepted Answer

First,molecular nitrogen (N₂)...

Question 16

Which of the following is not true about the anammox reaction?

Accepted Answer

A)  Anammox converts ammonia to nitrogen.
B)  Anammox is performed by symbiotic bacteria of leguminous plants.
C)  Anammox generates the highly reactive molecule hydrazine that is a component of rocket fuel.
D)  Anammox occursw anaerobically.
E)  The ultimate electron acceptor in anammox is nitrite.F) C) and D)
G) A) and D)

Question 17

The nitrogen atom in the indole ring of tryptophan is derived from which amino acid?

Accepted Answer

A)  Aspartic acid
B)  Glutamic acid
C)  Glutamine
D)  Asparagine
E)  ArginineF) A) and E)
G) None of the above

Question 18

Which of the following is not true of the reaction catalyzed by ribonucleotide reductase?

Accepted Answer

A)  Glutathione is part of the path of electron transfer.
B)  It acts on nucleoside diphosphates.
C)  Its mechanism involves formation of a free radical.
D)  There is a separate enzyme for each nucleotide (ADP,CDP,GDP,UDP) .
E)  Thioredoxin acts as an essential electron carrier.F) C) and D)
G) A) and B)

Question 19

Orotic aciduria is an inherited metabolic disease in which orotic acid (orotate) accumulates in the tissues,blood,and urine.The metabolic pathway in which the enzyme defect occurs is:

Accepted Answer

A)  epinephrine synthesis.
B)  purine breakdown.
C)  purine synthesis.
D)  pyrimidine breakdown.
E)  pyrimidine synthesis.F) C) and E)
G) A) and C) E

Question 20

Which one of the following statements is true of the biosynthetic pathway for purine nucleotides?

Accepted Answer

A)  CO2 does not participate in any of the steps in this pathway.
B)  Deoxyribonucleotides are formed from 5-phosphodeoxyribosyl 1-pyrophosphate.
C)  Inosinate is the purine nucleotide that is the precursor of both adenylate and guanylate.
D)  Orotic acid is an essential precursor for purine nucleotides.
E)  The amino acid valine is one of the precursors contributing to purine nucleotides.F) B) and D)
G) D) and E)

Exam 22: Biosynthesis of Amino Acids, nucleotides, and Related Molecules

The amino acid __________ and is an intermediate in the biosynthesis of _________.

Correct AnswerverifiedShow Answer

Which of the following is not a chemotherapeutic drug?

Correct AnswerverifiedShow Answer

Bile pigments are:

Correct AnswerverifiedShow Answer

Give the name and structure of the glycolytic or citric acid cycle intermediate that has the same carbon skeleton as (a)alanine, (b)glutamate, (c)aspartate.

Correct Answerverified(a)Pyruvate CH3-CO-...View AnswerShow Answer

Describe the pathway by which GMP is converted into GTP;show the co-substrates that are involved and name the enzymes.

Correct AnswerverifiedGMP + ATP GDP + ADP (nucleosi...View AnswerShow Answer

The most direct precursors of the nitrogens of UMP are:

Correct AnswerverifiedShow Answer

CMP,UMP,and TMP all have ________________ as a common precursor.

Correct AnswerverifiedB

Draw the structure of 5'-GMP.Indicate with an arrow the atom(s)derived from glutamine's amide group(s).

Correct AnswerverifiedThe structure of 5'-GMP is sho...View AnswerShow Answer

The hormones epinephrine and norepinephrine are derived biosynthetically from:

Correct AnswerverifiedShow Answer

An amino acid that does not derive its carbon skeleton,at least in part,from oxaloacetate is:

Correct AnswerverifiedShow Answer

Describe and contrast,with diagrams,concerted (cumulative)feedback regulation and sequential feedback inhibition.

Correct AnswerverifiedBoth are allosteric mechanisms to reduce...View AnswerShow Answer

Erythrose 4-phosphate is a precursor of:

Correct AnswerverifiedShow Answer

In which group are all the amino acids closely interrelated metabolically?

Correct AnswerverifiedE

Show the reaction catalyzed by glycine synthase,indicating the role of any cofactors that participate.

Correct AnswerverifiedCO2 + NH4View AnswerShow Answer

Trace the path of nitrogen from atmospheric N2 into glutamate.Name the intermediates (no structures necessary)and enzymes,and show any coenzymes involved.

Correct AnswerverifiedFirst,molecular nitrogen (N2)...View AnswerShow Answer

Which of the following is not true about the anammox reaction?

Correct AnswerverifiedShow Answer

The nitrogen atom in the indole ring of tryptophan is derived from which amino acid?

Correct AnswerverifiedShow Answer

Which of the following is not true of the reaction catalyzed by ribonucleotide reductase?

Correct AnswerverifiedShow Answer

Orotic aciduria is an inherited metabolic disease in which orotic acid (orotate) accumulates in the tissues,blood,and urine.The metabolic pathway in which the enzyme defect occurs is:

Correct AnswerverifiedE

Which one of the following statements is true of the biosynthetic pathway for purine nucleotides?

Correct AnswerverifiedShow Answer

The amino acid __ and is an intermediate in the biosynthesis of _.

Correct Answer
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(a)Pyruvate CH₃-CO-...
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GMP + ATP GDP + ADP (nucleosi...
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B

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The structure of 5'-GMP is sho...
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Both are allosteric mechanisms to reduce...
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E

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CO₂ + NH_{4View Answer}

Trace the path of nitrogen from atmospheric N₂ into glutamate.Name the intermediates (no structures necessary)and enzymes,and show any coenzymes involved.

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First,molecular nitrogen (N₂)...
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E

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