Question 1

Glutamate is the carbon skeleton precursor for the amino acids glutamine, proline, and ______________.

Accepted Answer

The answer of Glutamate is the carbon skeleton precursor for...

Question 2

Draw homocysteine.

Accepted Answer

The molecu

Question 3

The enzyme _______________ is regulated by cumulative feedback inhibition.

Accepted Answer

glutamine

Question 4

Which of the following is the original nitrogen source for the nitrogen found in amino acids?

Accepted Answer

A)  atmospheric nitrogen (N2) 
B)  tetrahydrofolate 
C)  glutamine 
D)  ammonia (NH3) 
E)  urea 
A)  atmospheric nitrogen (N2) 
B)  tetrahydrofolate 
C)  glutamine 
D)  ammonia (NH3) 
E)  urea

Question 5

Glycine condenses with succinyl CoA in the first step of ____________ synthesis.

Accepted Answer

A)  thiamine 
B)  histamine 
C)  glutathione 
D)  porphyrin 
E)  folate 
A)  thiamine 
B)  histamine 
C)  glutathione 
D)  porphyrin 
E)  folate

Question 6

Homocysteine is an intermediate in the synthesis of cysteine and _______________.

Accepted Answer

The answer of Homocysteine is an intermediate in the synthesis...

Question 7

What unusual (and not recommended) experiments were carried out by Shemin and colleagues?

Accepted Answer

Acting as a human guinea pig,

Question 8

Essential amino acids (for humans) differ from nonessential amino acids in that

Accepted Answer

A)  nonessential amino acids are synthesized in simple reaction pathways compared to complex pathways for most essential amino acids. 
B)  essential amino acids are generally synthesized directly from citric acid cycle intermediates, but not nonessential amino acids. 
C)  microorganisms and animals cannot synthesize essential amino acids but plants can. 
D)  animals cannot synthesize essential amino acids because they have lost the ability to carry out transamination reactions. 
E)  All of the answers are correct. 
A)  nonessential amino acids are synthesized in simple reaction pathways compared to complex pathways for most essential amino acids. 
B)  essential amino acids are generally synthesized directly from citric acid cycle intermediates, but not nonessential amino acids. 
C)  microorganisms and animals cannot synthesize essential amino acids but plants can. 
D)  animals cannot synthesize essential amino acids because they have lost the ability to carry out transamination reactions. 
E)  All of the answers are correct.

Question 9

The carbon skeletons used to synthesize amino acids are intermediates found in

Accepted Answer

A)  glycolysis. 
B)  glycogen metabolism. 
C)  citric acid cycle. 
D)  All the answers are correct. 
E)  glycolysis and citric acid cycle 
A)  glycolysis. 
B)  glycogen metabolism. 
C)  citric acid cycle. 
D)  All the answers are correct. 
E)  glycolysis and citric acid cycle

Question 10

What is the advantage of the enzymatic cascade for the regulation of glutamine synthetase activity?

Accepted Answer

This allows fine-tuning and am

Question 11

Describe the regulation of the enzyme threonine deaminase.

Accepted Answer

This enzyme is inhibited by isoleucine,

Question 12

Describe the structure and function of the FeMo cofactor.

Accepted Answer

This unusual redox center is the site of

Question 13

S-Adenosylmethionine carries _______________groups.

Accepted Answer

A)  methyl 
B)  CO2 
C)  ammonia 
D)  formyl 
E)  None of the answers is correct. 
A)  methyl 
B)  CO2 
C)  ammonia 
D)  formyl 
E)  None of the answers is correct.

Question 14

The α-amino group found in most amino acids comes from _______________by a transamination reaction.

Accepted Answer

The answer of The α-amino group found in most amino...

Question 15

Which of the following is a versatile carrier of several different one-carbon units?

Accepted Answer

A)  pyridoxal phosphate 
B)  biotin 
C)  tetrahydrofolate 
D)  coenzyme A 
E)  None of the answers is correct. 
A)  pyridoxal phosphate 
B)  biotin 
C)  tetrahydrofolate 
D)  coenzyme A 
E)  None of the answers is correct.

Question 16

What is catalytic substrate channeling?

Accepted Answer

Channeling increases the catalytic rate,

Question 17

An example of a reaction controlled by enzyme multiplicity is

Accepted Answer

A)  phosphorylation of asparagine by aspartokinases. 
B)  phosphorylation of aspartate by aspartokinases. 
C)  phosphorylation of glutamine by glutamine synthetase. 
D)  all of the above. 
E)  None of the answers is correct. 
A)  phosphorylation of asparagine by aspartokinases. 
B)  phosphorylation of aspartate by aspartokinases. 
C)  phosphorylation of glutamine by glutamine synthetase. 
D)  all of the above. 
E)  None of the answers is correct.

Question 18

Organisms capable of carrying out reduction of atmospheric nitrogen include

Accepted Answer

A)  some bacteria and archaea. 
B)  higher eukaryotic organisms, such as mammals. 
C)  all plants. 
D)  fungi, including yeasts and molds. 
E)  None of the answers is correct. 
A)  some bacteria and archaea. 
B)  higher eukaryotic organisms, such as mammals. 
C)  all plants. 
D)  fungi, including yeasts and molds. 
E)  None of the answers is correct.

Question 19

This amino acid, in high levels, is correlated with the damage of cells lining the blood vessels.

Accepted Answer

A)  serine 
B)  cysteine 
C)  S-adenosylmethionine 
D)  citrulline 
E)  homocysteine 
A)  serine 
B)  cysteine 
C)  S-adenosylmethionine 
D)  citrulline 
E)  homocysteine

Question 20

What caused the "madness" of King George III?

Accepted Answer

It is believed that he suffered from a p

Exam 24: The Biosynthesis of Amino Acids

Glutamate is the carbon skeleton precursor for the amino acids glutamine, proline, and ______________.

Draw homocysteine.

The enzyme _______________ is regulated by cumulative feedback inhibition.

Which of the following is the original nitrogen source for the nitrogen found in amino acids?

Glycine condenses with succinyl CoA in the first step of ____________ synthesis.

Homocysteine is an intermediate in the synthesis of cysteine and _______________.

What unusual (and not recommended) experiments were carried out by Shemin and colleagues?

Essential amino acids (for humans) differ from nonessential amino acids in that

The carbon skeletons used to synthesize amino acids are intermediates found in

What is the advantage of the enzymatic cascade for the regulation of glutamine synthetase activity?

Describe the regulation of the enzyme threonine deaminase.

Describe the structure and function of the FeMo cofactor.

S-Adenosylmethionine carries _______________groups.

The α-amino group found in most amino acids comes from _______________by a transamination reaction.

Which of the following is a versatile carrier of several different one-carbon units?

What is catalytic substrate channeling?

An example of a reaction controlled by enzyme multiplicity is

Organisms capable of carrying out reduction of atmospheric nitrogen include

This amino acid, in high levels, is correlated with the damage of cells lining the blood vessels.

What caused the "madness" of King George III?

Biochemistry: an Evolving Science

Protein Composition and Structure

Exploring Proteins and Proteomes

DNA, RNA, and the Flow of Genetic Information

Exploring Genes and Genomes

Exploring Evolution and Bioinformatics

Hemoglobin: a Portrait of a Protein in Action

Enzymes: Basic Concepts and Kinetics

Oxidative Phosphorylation

Catalytic Strategies

Regulatory Strategies

Carbohydrates

Lipids and Cell Membranes

Membrane Channels and Pumps

Signal-Transduction Pathways

Metabolism: Basic Concepts and Design

Glycolysis and Gluconeogenesis

The Citric Acid Cycle

The Light Reactions of Photosynthesis

The Calvin Cycle and the Pentose Phosphate Pathway

Glycogen Metabolism

Fatty Acid Metabolism

Protein Turnover and Amino Acid Catabolism

Nucleotide Biosynthesis

Biosynthesis of Membrane Lipids and Steroids

The Integration of Metabolism

DNA Replication, Repair, and Recombination

Rna Synthesis and Processing

Protein Synthesis

The Control of Gene Expression in Prokaryotes

The Control of Gene Expression in Eukaryotes

Sensory Systems

The Immune System

Molecular Motors

Drug Development

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