Question 1

The protein ________________stores iron, whereas the protein transferrin transports it.

Accepted Answer

ferritin

Question 2

What vitamin is the precursor for methylcobalamin?

Accepted Answer

A)  B2 
B)  B6 
C)  B7 
D)  B9 
E)  B12 
A)  B2 
B)  B6 
C)  B7 
D)  B9 
E)  B12 E

Question 3

How may have feedback inhibition processes evolved?

Accepted Answer

A)  duplication of genes encoding catalytic domains 
B)  evolution of homologous subunits in the enzyme catalyzing the committed step 
C)  linking specific regulatory domains to catalytic domains 
D)  linking of multiple regulatory domains to one another 
E)  All of the answers are correct. 
A)  duplication of genes encoding catalytic domains 
B)  evolution of homologous subunits in the enzyme catalyzing the committed step 
C)  linking specific regulatory domains to catalytic domains 
D)  linking of multiple regulatory domains to one another 
E)  All of the answers are correct. C

Question 4

In comparing transaminase enzymes, certain amino acids have been conserved. What are these amino acids, and how are they important in determining the proper chirality of the new amino acid?

Accepted Answer

Both a lysine and an arginine are conser

Question 5

What is enzyme multiplicity?

Accepted Answer

This is a strategy for regulation in whi

Question 6

The _______________ reaction establishes the stereochemistry at the α-carbon atom in amino acids.

Accepted Answer

The answer of The _______________ reaction establishes the stereochemistry at...

Question 7

Which of the following is a vasodilator that is derived from histidine?

Accepted Answer

A)  epinephrine 
B)  norepinephrine 
C)  histamine 
D)  adenosine 
E)  prostacyclin 
A)  epinephrine 
B)  norepinephrine 
C)  histamine 
D)  adenosine 
E)  prostacyclin

Question 8

What is the activated methyl cycle?

Accepted Answer

The methyl group on the side-chain of me

Question 9

Which of the following is a tripeptide that functions as an antioxidant?

Accepted Answer

A)  glutathione 
B)  aspartame 
C)  oxytocin 
D)  thyrotropin-releasing hormone 
E)  None of the answers is correct. 
A)  glutathione 
B)  aspartame 
C)  oxytocin 
D)  thyrotropin-releasing hormone 
E)  None of the answers is correct.

Question 10

Tryptophan is a precursor for the neurotransmitter(s)

Accepted Answer

A)  serotonin. 
B)  norepinephrine. 
C)  adenine. 
D)  $\gamma$-aminobutyric acid. 
E)  None of the answers is correct. 
A)  serotonin. 
B)  norepinephrine. 
C)  adenine. 
D)  $\gamma$-aminobutyric acid. 
E)  None of the answers is correct.

Question 11

The enzyme _______________ contains a selenium analogue of cysteine.

Accepted Answer

glutathion

Question 12

What molecule is an activated form of ribose phosphate and a precursor for histidine?

Accepted Answer

A)  ribose triphosphate 
B)  PRPP (5-phosphoribosyl-1-pyrophosphate) 
C)  ATP 
D)  cyclic AMP 
E)  None of the answers is correct. 
A)  ribose triphosphate 
B)  PRPP (5-phosphoribosyl-1-pyrophosphate) 
C)  ATP 
D)  cyclic AMP 
E)  None of the answers is correct.

Question 13

What amino acid is added to indole in the biosynthesis of tryptophan?

Accepted Answer

A)  glutamine 
B)  serine 
C)  tyrosine 
D)  alanine 
E)  None of the answers is correct. 
A)  glutamine 
B)  serine 
C)  tyrosine 
D)  alanine 
E)  None of the answers is correct.

Question 14

Nitric oxide

Accepted Answer

A)  is a short-lived signal molecule. 
B)  is generated by the oxidation of lysine. 
C)  requires NADP+ and O2 for synthesis. 
D)  is metabolized be reaction with ornithine. 
E)  All of the answers are correct. 
A)  is a short-lived signal molecule. 
B)  is generated by the oxidation of lysine. 
C)  requires NADP+ and O2 for synthesis. 
D)  is metabolized be reaction with ornithine. 
E)  All of the answers are correct.

Question 15

What common biochemical strategy allows ammonia to be generated for use within the same enzyme?

Accepted Answer

A)  ammonia fixation 
B)  glutamine hydrolysis 
C)  ammonia activation 
D)  glutamate hydrolysis 
E)  None of the answers is correct. 
A)  ammonia fixation 
B)  glutamine hydrolysis 
C)  ammonia activation 
D)  glutamate hydrolysis 
E)  None of the answers is correct.

Question 16

Methyl, methylene, and _______________ units can be carried by tetrahydrofolate.

Accepted Answer

The answer of Methyl, methylene, and _______________ units can be...

Question 17

What do S-adenosylmethionine and fruit ripening have in common?

Accepted Answer

S-Adenosylmethionine is a prec

Question 18

Although nitrogen is abundant in the form of atmospheric nitrogen, it presents a fundamental problem for use in biological systems. What is the problem, and how is it resolved?

Accepted Answer

N₂ is a remarkably inert molecule and so

Question 19

What process converts N2 to NH3?

Accepted Answer

A)  urea cycle 
B)  glutamine hydrolysis 
C)  denitrification 
D)  nitrogen fixation 
E)  None of the answers is correct. 
A)  urea cycle 
B)  glutamine hydrolysis 
C)  denitrification 
D)  nitrogen fixation 
E)  None of the answers is correct.

Question 20

What molecule is the precursor for the biosynthesis of serine, cysteine, and glycine?

Accepted Answer

A)  pyruvate 
B)  oxaloacetate 
C)  $\alpha$-ketoglutarate 
D)  glyceraldehyde-3-phosphate 
E)  3-phosphoglycerate 
A)  pyruvate 
B)  oxaloacetate 
C)  $\alpha$-ketoglutarate 
D)  glyceraldehyde-3-phosphate 
E)  3-phosphoglycerate

Exam 24: The Biosynthesis of Amino Acids

The protein ________________stores iron, whereas the protein transferrin transports it.

What vitamin is the precursor for methylcobalamin?

How may have feedback inhibition processes evolved?

In comparing transaminase enzymes, certain amino acids have been conserved. What are these amino acids, and how are they important in determining the proper chirality of the new amino acid?

What is enzyme multiplicity?

The _______________ reaction establishes the stereochemistry at the α-carbon atom in amino acids.

Which of the following is a vasodilator that is derived from histidine?

What is the activated methyl cycle?

Which of the following is a tripeptide that functions as an antioxidant?

Tryptophan is a precursor for the neurotransmitter(s)

The enzyme _______________ contains a selenium analogue of cysteine.

What molecule is an activated form of ribose phosphate and a precursor for histidine?

What amino acid is added to indole in the biosynthesis of tryptophan?

Nitric oxide

What common biochemical strategy allows ammonia to be generated for use within the same enzyme?

Methyl, methylene, and _______________ units can be carried by tetrahydrofolate.

What do S-adenosylmethionine and fruit ripening have in common?

Although nitrogen is abundant in the form of atmospheric nitrogen, it presents a fundamental problem for use in biological systems. What is the problem, and how is it resolved?

What process converts N2 to NH3?

What molecule is the precursor for the biosynthesis of serine, cysteine, and glycine?

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

Filters

What process converts N₂ to NH₃?