Question 1

What is the amino acid error rate in protein synthesis? Is this rate logical in evolutionary terms of function?

Accepted Answer

The error rate is approximatel

Question 2

Protein synthesis takes place on

Accepted Answer

A)  lysozomes. 
B)  nuclear pores. 
C)  vacuoles. 
D)  ribosomes 
E)  None of the answers is correct. 
A)  lysozomes. 
B)  nuclear pores. 
C)  vacuoles. 
D)  ribosomes 
E)  None of the answers is correct.

Question 3

How is a high level of fidelity maintained in attaching the amino acids to the tRNA structure?

Accepted Answer

The reaction has very high fidelity in r

Question 4

What factor(s) is (are) necessary for the correct placement of the mRNA and initiating tRNA on the ribosome?

Accepted Answer

A)  IF1 
B)  IF2 
C)  IF3 
D)  IF1 and IF2 
E)  All the answers are correct. 
A)  IF1 
B)  IF2 
C)  IF3 
D)  IF1 and IF2 
E)  All the answers are correct.

Question 5

What sequence identifies a protein for translocation across the ER?

Accepted Answer

A)  signal sequence 
B)  Shine-Dalgarno sequence 
C)  poly-A sequence 
D)  endoplasmic sequence 
E)  cargo sequence 
A)  signal sequence 
B)  Shine-Dalgarno sequence 
C)  poly-A sequence 
D)  endoplasmic sequence 
E)  cargo sequence

Question 6

What is the function of the B segment of diphtheria toxin?

Accepted Answer

A)  mimics aminoacyl-tRNA, thus causing premature termination of protein synthesis 
B)  cleaving tRNA 
C)  allowing the A fragment to enter the cell 
D)  covalent modification of elongation factor 2 
E)  None of the answers is correct. 
A)  mimics aminoacyl-tRNA, thus causing premature termination of protein synthesis 
B)  cleaving tRNA 
C)  allowing the A fragment to enter the cell 
D)  covalent modification of elongation factor 2 
E)  None of the answers is correct.

Question 7

The error frequency of protein synthesis is approximately _____________.

Accepted Answer

10 <sup>-<

Question 8

Which of the following is (are) required for initiation of protein synthesis in bacteria?

Accepted Answer

A)  mRNA 
B)  the 30S subunit 
C)  fmet-tRNAf 
D)  GTP 
E)  All of the answers are correct. 
A)  mRNA 
B)  the 30S subunit 
C)  fmet-tRNAf 
D)  GTP 
E)  All of the answers are correct.

Question 9

What term describes the RNA-directed process of protein synthesis?

Accepted Answer

A)  transcription 
B)  translation 
C)  Merrifield synthesis 
D)  ribozyme-directed protein synthesis 
E)  None of the answers is correct. 
A)  transcription 
B)  translation 
C)  Merrifield synthesis 
D)  ribozyme-directed protein synthesis 
E)  None of the answers is correct.

Question 10

The actual three-dimensional structure of tRNA is

Accepted Answer

A)  overall L-shaped. 
B)  cloverleaf. 
C)  twisted triple helix. 
D)  cylindrical. 
E)  None of the answers is correct. 
A)  overall L-shaped. 
B)  cloverleaf. 
C)  twisted triple helix. 
D)  cylindrical. 
E)  None of the answers is correct.

Question 11

Where is the amino acid attached to a tRNA molecule?

Accepted Answer

A)  3'-hydroxyl of an adenine residue 
B)  5'-hydroxyl of a uridine residue 
C)  2'-hydroxyl of a guanine residue 
D)  3'-hydroxyl of a cytosine residue 
E)  2'-hydroxyl of a guanine residue. 
A)  3'-hydroxyl of an adenine residue 
B)  5'-hydroxyl of a uridine residue 
C)  2'-hydroxyl of a guanine residue 
D)  3'-hydroxyl of a cytosine residue 
E)  2'-hydroxyl of a guanine residue.

Question 12

The ribosome is thought to be

Accepted Answer

A)  an example of a catalyst that has survived from the RNA world. 
B)  unique to eukaryotes. 
C)  a ribozyme. 
D)  a protein catalyst. 
E)  an example of a catalyst that has survived from the RNA world and a ribozyme. 
A)  an example of a catalyst that has survived from the RNA world. 
B)  unique to eukaryotes. 
C)  a ribozyme. 
D)  a protein catalyst. 
E)  an example of a catalyst that has survived from the RNA world and a ribozyme.

Question 13

Proteins destined for extracellular release must first bind to the _________________ in the lumen of the ER.

Accepted Answer

The answer of Proteins destined for extracellular release must first...

Question 14

The rate of translation in E. coli is ________ amino acids per second.

Accepted Answer

A)  5 
B)  20 
C)  50 
D)  120 
E)  None of the answers is correct. 
A)  5 
B)  20 
C)  50 
D)  120 
E)  None of the answers is correct.

Question 15

The signal sequence that marks a protein for translocation across the endoplasmic reticulum membrane is located near the ____________________ end of the protein.

Accepted Answer

N-terminal

Question 16

What is the direction of translation of mRNA?

Accepted Answer

A)  bidirectional 
B)  5' to 3' 
C)  3' to 5' 
D)  5' to 3' in bacteria, 3' to 5' in eukaryotes 
E)  5' to 3' in eukaryotes, 3' to 5' in bacteria 
A)  bidirectional 
B)  5' to 3' 
C)  3' to 5' 
D)  5' to 3' in bacteria, 3' to 5' in eukaryotes 
E)  5' to 3' in eukaryotes, 3' to 5' in bacteria

Question 17

Which of the following E. coli proteins is responsible for translocation of the mRNA as a result of a conformation change due to the hydrolysis of GTP?

Accepted Answer

A)  RRF 
B)  EF-Tu 
C)  EF-G 
D)  Shine-Dalgarno 
E)  None of the answers is correct. 
A)  RRF 
B)  EF-Tu 
C)  EF-G 
D)  Shine-Dalgarno 
E)  None of the answers is correct.

Question 18

How does puromycin inhibit protein synthesis?

Accepted Answer

Puromycin resembles an amino acid attach

Question 19

Initiation, elongation, and termination all require factors that are members of the ______________________ family.

Accepted Answer

The answer of Initiation, elongation, and termination all require factors...

Question 20

Where is the attachment site and where is the anticodon loop with respect to the nucleotide sequence and with respect to the L-shaped structure of tRNA?

Accepted Answer

The amino acid is attached to the CCA se

Exam 30: Protein Synthesis

What is the amino acid error rate in protein synthesis? Is this rate logical in evolutionary terms of function?

Protein synthesis takes place on

How is a high level of fidelity maintained in attaching the amino acids to the tRNA structure?

What factor(s) is (are) necessary for the correct placement of the mRNA and initiating tRNA on the ribosome?

What sequence identifies a protein for translocation across the ER?

What is the function of the B segment of diphtheria toxin?

The error frequency of protein synthesis is approximately _____________.

Which of the following is (are) required for initiation of protein synthesis in bacteria?

What term describes the RNA-directed process of protein synthesis?

The actual three-dimensional structure of tRNA is

Where is the amino acid attached to a tRNA molecule?

The ribosome is thought to be

Proteins destined for extracellular release must first bind to the _________________ in the lumen of the ER.

The rate of translation in E. coli is ________ amino acids per second.

The signal sequence that marks a protein for translocation across the endoplasmic reticulum membrane is located near the ____________________ end of the protein.

What is the direction of translation of mRNA?

Which of the following E. coli proteins is responsible for translocation of the mRNA as a result of a conformation change due to the hydrolysis of GTP?

How does puromycin inhibit protein synthesis?

Initiation, elongation, and termination all require factors that are members of the ______________________ family.

Where is the attachment site and where is the anticodon loop with respect to the nucleotide sequence and with respect to the L-shaped structure of tRNA?

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

The Biosynthesis of Amino Acids

Nucleotide Biosynthesis

Biosynthesis of Membrane Lipids and Steroids

The Integration of Metabolism

DNA Replication, Repair, and Recombination

Rna Synthesis and Processing

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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