Question 1

Activation of amino acids

Accepted Answer

A)  produces a pyrophosphate byproduct. 
B)  produces an inorganic phosphate. 
C)  produces a cyclic AMP. 
D)  does not involve the release of energy. 
A)  produces a pyrophosphate byproduct. 
B)  produces an inorganic phosphate. 
C)  produces a cyclic AMP. 
D)  does not involve the release of energy. A

Question 2

After peptide bond formation takes place, what step is necessary for continuation of protein synthesis?

Accepted Answer

A)  binding of uncharged tRNA to the ribosome 
B)  binding of EF−Tu 
C)  binding of EF−Ts 
D)  translocation of the ribosome 
A)  binding of uncharged tRNA to the ribosome 
B)  binding of EF−Tu 
C)  binding of EF−Ts 
D)  translocation of the ribosome D

Question 3

In bacteria, each mRNA will bind to only one ribosome at a time.

Accepted Answer

A) True 
 B)False  False

Question 4

How many codons are known for each amino acid?

Accepted Answer

A)  1 only 
B)  2 only 
C)  2 to 4 depending on the nature of the amino acid 
D)  1 to 6 depending on the nature of the amino acid 
A)  1 only 
B)  2 only 
C)  2 to 4 depending on the nature of the amino acid 
D)  1 to 6 depending on the nature of the amino acid

Question 5

Chaperones assist in protein folding by preventing aggregation of proteins before folding is completed.

Accepted Answer

A) True 
 B)False

Question 6

Which antibiotic confirmed that the growing peptide chain is transferred to the amino group of the incoming tRNA?

Accepted Answer

A)  Puromycin 
B)  Streptomycin 
C)  Cyclohexamide 
D)  None of these antibiotics was useful for studying the mechanism of protein synthesis. 
E)  None of these antibiotics actually interferes with peptide transfer. 
A)  Puromycin 
B)  Streptomycin 
C)  Cyclohexamide 
D)  None of these antibiotics was useful for studying the mechanism of protein synthesis. 
E)  None of these antibiotics actually interferes with peptide transfer.

Question 7

The ribosome is actually a ribozyme.

Accepted Answer

A) True 
 B)False

Question 8

Which of the following is not a function of initiation factors in E. coli?

Accepted Answer

A)  Prevent the ribosomal subunits from binding together. 
B)  Lead the initial tRNA to its correct position on the large subunit of the ribosome. 
C)  Help the mRNA to bind to the tRNA. 
D)  Carry GTP to provide energy for certain steps in the initiation process. 
E)  The initiation factors do all of these. 
A)  Prevent the ribosomal subunits from binding together. 
B)  Lead the initial tRNA to its correct position on the large subunit of the ribosome. 
C)  Help the mRNA to bind to the tRNA. 
D)  Carry GTP to provide energy for certain steps in the initiation process. 
E)  The initiation factors do all of these.

Question 9

In the wobble phenomenon, the base that wobbles is found in

Accepted Answer

A)  the tRNA. 
B)  the mRNA 
C)  either the tRNA or the mRNA. 
A)  the tRNA. 
B)  the mRNA 
C)  either the tRNA or the mRNA.

Question 10

Which of following best describes the two-step process for adding amino acids to tRNAs AA = amino acid, Pi = phosphate, PPi = pyrophosphate

Accepted Answer

A)  AA + ATP → AA−P + ADP; AA−P + tRNA → AA−tRNA + Pi 
B)  AA + ATP → AA−AMP + PPi; AA−AMP + tRNA → AA−tRNA + AMP 
C)  tRNA + ATP → tRNA−P + ADP; tRNA−P + AA → AA−tRNA + Pi 
D)  tRNA + ATP → tRNA−AMP + PPi; tRNA−AMP + AA → AA−tRNA + AMP 
A)  AA + ATP → AA−P + ADP; AA−P + tRNA → AA−tRNA + Pi 
B)  AA + ATP → AA−AMP + PPi; AA−AMP + tRNA → AA−tRNA + AMP 
C)  tRNA + ATP → tRNA−P + ADP; tRNA−P + AA → AA−tRNA + Pi 
D)  tRNA + ATP → tRNA−AMP + PPi; tRNA−AMP + AA → AA−tRNA + AMP

Question 11

During elongation, tRNA binds initially to the

Accepted Answer

A)  "A" site on the ribosome. 
B)  "P" site on the ribosome. 
C)  "E" site on the ribosome. 
A)  "A" site on the ribosome. 
B)  "P" site on the ribosome. 
C)  "E" site on the ribosome.

Question 12

What is the maximum number of amino acids that can be specified by a codon consisting of a sequence of two bases?

Accepted Answer

A)  4 
B)  8 
C)  16 
D)  20 
A)  4 
B)  8 
C)  16 
D)  20

Question 13

Which category of RNA carries amino acids for the process of translation?

Accepted Answer

A)  mRNA 
B)  rRNA 
C)  snRNA 
D)  tRNA 
A)  mRNA 
B)  rRNA 
C)  snRNA 
D)  tRNA

Question 14

An aminoacyl-adenylate contains

Accepted Answer

A)  an ester bond 
B)  an acid anhydride bond 
C)  an amide bond 
D)  an ether bond 
A)  an ester bond 
B)  an acid anhydride bond 
C)  an amide bond 
D)  an ether bond

Question 15

Ribosomal frameshifting in Influenza Virus A is caused by the fact that

Accepted Answer

A)  the virus has a modified genetic code 
B)  the virus attacks the mRNA 
C)  the ribosome reaches a rare arginine codon and stalls out 
D)  none of these 
A)  the virus has a modified genetic code 
B)  the virus attacks the mRNA 
C)  the ribosome reaches a rare arginine codon and stalls out 
D)  none of these

Question 16

Which of the following is not required for the elongation phase of protein synthesis?

Accepted Answer

A)  GTP 
B)  fmet-tRNAfmet 
C)  peptidyl transferase 
D)  mRNA 
A)  GTP 
B)  fmet-tRNAfmet 
C)  peptidyl transferase 
D)  mRNA

Question 17

Which of the following best describes the assembly process to initiate translation in prokaryotes?

Accepted Answer

A)  small ribosome subunit associates with large subunit; mRNA associates next; IFs bring in first f-Met-tRNA; bound NTP hydrolyzed. 
B)  IF binds f-Met-tRNA; small ribosome subunit associates next; mRNA associates next; then large subunit; bound NTP hydrolyzed. 
C)  IF w/ bound NTP binds f-Met-tRNA; mRNA associates next; small subunit associates next; bound NTP hydrolyzed; large subunit associates. 
D)  small subunit associates with mRNA; IF w/ bound NTP brings in first f-Met-tRNA; IF then hydrolyses bound NTP; large subunit associates 
A)  small ribosome subunit associates with large subunit; mRNA associates next; IFs bring in first f-Met-tRNA; bound NTP hydrolyzed. 
B)  IF binds f-Met-tRNA; small ribosome subunit associates next; mRNA associates next; then large subunit; bound NTP hydrolyzed. 
C)  IF w/ bound NTP binds f-Met-tRNA; mRNA associates next; small subunit associates next; bound NTP hydrolyzed; large subunit associates. 
D)  small subunit associates with mRNA; IF w/ bound NTP brings in first f-Met-tRNA; IF then hydrolyses bound NTP; large subunit associates

Question 18

Each tRNA molecule has a separate activating enzyme.

Accepted Answer

A) True 
 B)False

Question 19

At what point does the formylation reaction take place to produce N-formylmethionine?

Accepted Answer

A)  On the free amino acid prior to its addition to a tRNA. 
B)  After methionine has been added to a specific tRNA. 
C)  After the methionine-tRNA adduct has complexed with the ribosome. 
D)  After the first peptide bond is formed on the ribosome. 
A)  On the free amino acid prior to its addition to a tRNA. 
B)  After methionine has been added to a specific tRNA. 
C)  After the methionine-tRNA adduct has complexed with the ribosome. 
D)  After the first peptide bond is formed on the ribosome.

Question 20

Which of the following is not a prokaryotic elongation factor?

Accepted Answer

A)  EF-Tu 
B)  EF-Ts 
C)  EF-G 
D)  EF-P 
E)  all of these are prokaryotic elognation factors 
A)  EF-Tu 
B)  EF-Ts 
C)  EF-G 
D)  EF-P 
E)  all of these are prokaryotic elognation factors

Exam 12: Protein Synthesis: Translation of the Genetic Message

Activation of amino acids

After peptide bond formation takes place, what step is necessary for continuation of protein synthesis?

In bacteria, each mRNA will bind to only one ribosome at a time.

How many codons are known for each amino acid?

Chaperones assist in protein folding by preventing aggregation of proteins before folding is completed.

Which antibiotic confirmed that the growing peptide chain is transferred to the amino group of the incoming tRNA?

The ribosome is actually a ribozyme.

Which of the following is not a function of initiation factors in E. coli?

In the wobble phenomenon, the base that wobbles is found in

Which of following best describes the two-step process for adding amino acids to tRNAs AA = amino acid, Pi = phosphate, PPi = pyrophosphate

During elongation, tRNA binds initially to the

What is the maximum number of amino acids that can be specified by a codon consisting of a sequence of two bases?

Which category of RNA carries amino acids for the process of translation?

An aminoacyl-adenylate contains

Ribosomal frameshifting in Influenza Virus A is caused by the fact that

Which of the following is not required for the elongation phase of protein synthesis?

Which of the following best describes the assembly process to initiate translation in prokaryotes?

Each tRNA molecule has a separate activating enzyme.

At what point does the formylation reaction take place to produce N-formylmethionine?

Which of the following is not a prokaryotic elongation factor?

Biochemistry and the Organization of Cells

Water: the Solvent for Biochemical Reactions

Amino Acids and Peptides

The Three-Dimensional Structure of Proteins

Protein Purification and Characterization Techniques

The Behavior of Proteins: Enzymes

The Behavior of Proteins: Enzymes, Mechanisms, and Control

Lipids and Proteins Are Associated in Biological Membranes

Nucleic Acids: How Structure Conveys Information

Biosynthesis of Nucleic Acids: Replication

Transcription of the Genetic Code: Biosynthesis of RNA

Nucleic Acid Biotechnology Techniques

Viruses, Cancer, and Immunology

The Importance of Energy Changes and Electron Transfer in Metabolism

Carbohydrates

Glycolysis

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Lipid Metabolism

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism: Cellular Signaling

Filters

Which of following best describes the two-step process for adding amino acids to tRNAs AA = amino acid, P_i = phosphate, PP_i = pyrophosphate