Question 1

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 glutamate 
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 glutamate E

Question 2

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

Accepted Answer

A) adenosine 
B) aspartate 
C) glutamine 
D) inosine 
E) S-adenosyl methionine 
A) adenosine 
B) aspartate 
C) glutamine 
D) inosine 
E) S-adenosyl methionine B

Question 3

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

Question 4

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. 
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.

Question 5

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

Accepted Answer

CO₂ + NH₄

Question 6

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;glutathione 
A) histidine;purines 
B) glycine;heme 
C) serine;heme 
D) serine;sphingosine 
E) glutamine;glutathione

Question 7

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

Question 8

Erythrose 4-phosphate is a precursor of:

Accepted Answer

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

Question 9

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

Accepted Answer

Both are allosteric mechanisms to reduce

Question 10

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) Arginine 
A) Aspartic acid 
B) Glutamic acid 
C) Glutamine 
D) Asparagine 
E) Arginine

Question 11

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 @#LAT-DLM& GDP + ADP (nucleosi

Question 12

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 13

The hormones epinephrine and norepinephrine are derived biosynthetically from:

Accepted Answer

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

Question 14

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 15

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. 
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.

Question 16

Which of the following is not a chemotherapeutic drug?

Accepted Answer

A) Azaserine 
B) Allopurinol 
C) Fluorouracil 
D) Methotrexate 
E) Acivicin 
A) Azaserine 
B) Allopurinol 
C) Fluorouracil 
D) Methotrexate 
E) Acivicin

Question 17

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 18

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

Question 19

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. 
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.

Question 20

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. 
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.

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

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

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

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:

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

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

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

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

Erythrose 4-phosphate is a precursor of:

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

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

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

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.

The hormones epinephrine and norepinephrine are derived biosynthetically from:

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

Bile pigments are:

Which of the following is not a chemotherapeutic drug?

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

The most direct precursors of the nitrogens of UMP are:

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

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

The Foundations of Biochemistry

Water

Amino Acids, peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Enzymes

Carbohydrates and Glycobiology

Nucleotides and Nucleic Acids

Recombinant Dna Technology

Lipids

Biological Membranes and Transport

Biosignaling

Principles of Bioenergetics

Glycolysis, gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Fatty Acid Catabolism

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Integration and Hormonal Regulation of Mammalian Metabolism

Genes and Chromosomes

Dna Metabolism

Rna Metabolism

Protein Metabolism

Regulation of Gene Expression

Filters

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

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