Question 1

The correct amino acid is covalently attached to a tRNA by the corresponding ______ which is specific for each ______.

Accepted Answer

A) aminoacyl-tRNA synthetase (aaRS);amino acid 
B) aminoacyl-tRNA synthetase (aaRS);species 
C) elongation factor;amino acid 
D) elongation factor;species 
E) none of the above 
A) aminoacyl-tRNA synthetase (aaRS);amino acid 
B) aminoacyl-tRNA synthetase (aaRS);species 
C) elongation factor;amino acid 
D) elongation factor;species 
E) none of the above

Question 2

The triplet code allows many amino acids to be specified by more than one codon.Such a code is said to be

Accepted Answer

A) replicative. 
B) synonymous. 
C) duplicative. 
D) universal. 
E) degenerate. 
A) replicative. 
B) synonymous. 
C) duplicative. 
D) universal. 
E) degenerate.

Question 3

Matching
Choose the correct answer from the list.Not all the answers will be used.

-The fidelity of amino acid attachment to a tRNA is enhanced by the ______ ability of the corresponding aaRS.

Accepted Answer

A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf 
A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf

Question 4

Proteins are properly folded with the assistance of

Accepted Answer

A) protein-conducting channels (PCCs). 
B) small ubiquitin-related modifiers (SUMOs). 
C) trigger factors. 
D) chaperones. 
E) signal recognition particles (SRPs). 
A) protein-conducting channels (PCCs). 
B) small ubiquitin-related modifiers (SUMOs). 
C) trigger factors. 
D) chaperones. 
E) signal recognition particles (SRPs).

Question 5

Which linkage best describes the covalent bond between an amino acid (AA)and its cognate tRNA?

Accepted Answer

A) amino group of AA linked to 5' -OH of tRNA 
B) amino group of AA linked to 5' phosphate of tRNA 
C) carboxyl group of AA linked to 3' -OH of tRNA 
D) carboxyl group of AA linked to 3' phosphate of tRNA 
E) none of the above 
A) amino group of AA linked to 5' -OH of tRNA 
B) amino group of AA linked to 5' phosphate of tRNA 
C) carboxyl group of AA linked to 3' -OH of tRNA 
D) carboxyl group of AA linked to 3' phosphate of tRNA 
E) none of the above

Question 6

Which of the following is a function of the ribosome?
(I)bind mRNA and allow codon recognition
(II)mediate the binding of proteins necessary for initiation,elongation,and termination
(III)catalyze synthesis of peptide bonds
(IV)translocates such that multiple codons can be read

Accepted Answer

A) I only 
B) I,II 
C) I,IV 
D) II only 
E) I,II,III,IV 
A) I only 
B) I,II 
C) I,IV 
D) II only 
E) I,II,III,IV

Question 7

Which of the following best describes the preparation of fMet-tRNAfmet for translation in prokaryotes?

Accepted Answer

A) Met is first formylated,then added to a tRNA specific for the start codon that differs from that designed to carry Met. 
B) Met is first added to a tRNA specific for the start codon that differs from that designed to carry Met,then is formylated. 
C) Met is first formylated,then added to a "regular" tRNA;the fact that it has the formyl group allows use in the initiation codon. 
D) Met is first added to a "regular" tRNA,then is formylated;the fact that it has the formyl group allows use in the initiation codon. 
E) f-Met isn't used in prokaryotes,only in eukaryotes. 
A) Met is first formylated,then added to a tRNA specific for the start codon that differs from that designed to carry Met. 
B) Met is first added to a tRNA specific for the start codon that differs from that designed to carry Met,then is formylated. 
C) Met is first formylated,then added to a "regular" tRNA;the fact that it has the formyl group allows use in the initiation codon. 
D) Met is first added to a "regular" tRNA,then is formylated;the fact that it has the formyl group allows use in the initiation codon. 
E) f-Met isn't used in prokaryotes,only in eukaryotes.

Question 8

Matching
Choose the correct answer from the list.Not all the answers will be used.

-The start codon is usually ______.

Accepted Answer

A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf 
A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf

Question 9

Matching
Choose the correct answer from the list.Not all the answers will be used.

-EF-Tu binds all ______ aminoacyl tRNAs but that of tRNAsec.

Accepted Answer

A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf 
A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf

Question 10

Which of the following is(are)used to assist in protein folding?
(I)calnexin
(II)calreticulin
(III)DnaK
(IV)GroEL

Accepted Answer

A) I,II 
B) III,IV 
C) II,IV 
D) I,III 
E) I,II,III,IV 
A) I,II 
B) III,IV 
C) II,IV 
D) I,III 
E) I,II,III,IV

Question 11

In E.coli,which of the following factors function to ensure the proper binding of tRNAfMet during mRNA binding and ribosomal subunit assembly?
(I)IF-1
(II)IF-2
(III)IF-3
(IV)EF-Ts

Accepted Answer

A) I only 
B) I,II 
C) I,III 
D) II,IV 
E) I,II,III 
A) I only 
B) I,II 
C) I,III 
D) II,IV 
E) I,II,III

Question 12

Matching
Choose the correct answer from the list.Not all the answers will be used.

-Translation termination requires ______ that recognize Stop codons.

Accepted Answer

A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf 
A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf

Question 13

What happens when a stop codon is reached by a ribosome?

Accepted Answer

A) A termination tRNAter binds to the codon and is used to release the growing peptide from the P site tRNA.The ribosome then is likely to dissociate. 
B) A termination tRNAter binds to the codon and the growing peptide is transferred to it.When the peptidyl-tRNAter reaches the P site,the ribosome is signaled to release the protein.The ribosome then is likely to dissociate. 
C) A termination tRNAter binds to the codon and the growing peptide is transferred to it.When the peptidyl-tRNAter reaches the P site,the ribosome dissociates.A separate peptidyl transferase then releases the protein from tRNAter. 
D) A release factor binds to the codon and is used to release the growing peptide from the P site tRNA. 
E) A release factor binds to the codon and the ribosome dissociates.A separate peptidyl transferase then releases the protein from the last tRNA to which was attached. 
A) A termination tRNAter binds to the codon and is used to release the growing peptide from the P site tRNA.The ribosome then is likely to dissociate. 
B) A termination tRNAter binds to the codon and the growing peptide is transferred to it.When the peptidyl-tRNAter reaches the P site,the ribosome is signaled to release the protein.The ribosome then is likely to dissociate. 
C) A termination tRNAter binds to the codon and the growing peptide is transferred to it.When the peptidyl-tRNAter reaches the P site,the ribosome dissociates.A separate peptidyl transferase then releases the protein from tRNAter. 
D) A release factor binds to the codon and is used to release the growing peptide from the P site tRNA. 
E) A release factor binds to the codon and the ribosome dissociates.A separate peptidyl transferase then releases the protein from the last tRNA to which was attached.

Question 14

Codons that do not specify amino acids but signal the ribosome to terminate polypeptide chain elongation are termed

Accepted Answer

A) frameshifts. 
B) anticodon. 
C) Stop codons. 
D) suppressors. 
E) terminators. 
A) frameshifts. 
B) anticodon. 
C) Stop codons. 
D) suppressors. 
E) terminators.

Question 15

Matching
Choose the correct answer from the list.Not all the answers will be used.

-Some proteins are synthesized as inactive precursors called ______.

Accepted Answer

A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf 
A)  AUG 
B)  sense 
C)  release factors 
D)  noninitiator 
E)  hairpin
F) preproteins
G) genetic code
H) penicillin
I) proproteins
J) proofreading
K) UUA
L) synonyms
M) nucleotide cypher
N) streptomycin
O) nonsense
P) revising
Q) cloverleaf

Question 16

Which of following describes proofreading for the addition of amino acids (AAs)to the growing peptide?

Accepted Answer

A) An RNA component of the ribosome ensures that the correct AA is associated with the A site before addition occurs. 
B) An RNA component of the ribosome ensures that the correct AA has been added,but before the peptidyl-tRNA is shifted to the P site. 
C) The EF-Tu • GTP complex ensures that the correct AA is associated with the A site before addition occurs. 
D) EF-G ensures that the correct AA has been added,but before the peptidyl-tRNA is shifted to the P -site. 
E) No proofreading of this process occurs. 
A) An RNA component of the ribosome ensures that the correct AA is associated with the A site before addition occurs. 
B) An RNA component of the ribosome ensures that the correct AA has been added,but before the peptidyl-tRNA is shifted to the P site. 
C) The EF-Tu • GTP complex ensures that the correct AA is associated with the A site before addition occurs. 
D) EF-G ensures that the correct AA has been added,but before the peptidyl-tRNA is shifted to the P -site. 
E) No proofreading of this process occurs.

Question 17

The signal recognition particle (SRP)is a _____,and its function is to ______.

Accepted Answer

A) DNA:protein complex,transport proteins into the eukaryotic nucleus 
B) multisubunit protein,modify proteins 
C) ribosome complex,catalyze posttranslational modification 
D) ribonucleoprotein,bind the N-terminal end of growing polypeptides for membrane translocation 
E) none of the above 
A) DNA:protein complex,transport proteins into the eukaryotic nucleus 
B) multisubunit protein,modify proteins 
C) ribosome complex,catalyze posttranslational modification 
D) ribonucleoprotein,bind the N-terminal end of growing polypeptides for membrane translocation 
E) none of the above

Question 18

The sequence steps involved in elongation of the newly synthesized protein are ordered as follows: (Note: AA=amino acid)

Accepted Answer

A) AA-tRNA binding,peptide bond formation,translocation,tRNA release. 
B) translocation,AA-tRNA binding,tRNA release,peptide bond formation. 
C) tRNA release,AA-tRNA binding,translocation,peptide bond formation. 
D) translocation,peptide bond formation,AA-tRNA binding,tRNA release. 
E) peptide bond formation,tRNA release,AA-tRNA binding,translocation. 
A) AA-tRNA binding,peptide bond formation,translocation,tRNA release. 
B) translocation,AA-tRNA binding,tRNA release,peptide bond formation. 
C) tRNA release,AA-tRNA binding,translocation,peptide bond formation. 
D) translocation,peptide bond formation,AA-tRNA binding,tRNA release. 
E) peptide bond formation,tRNA release,AA-tRNA binding,translocation.

Question 19

Which of the following is NOT associated with eukaryotic translation initiation?

Accepted Answer

A) Shine-Dalgarno sequence 
B) a formylated Met−tRNAfmet 
C) base pairing between the mRNA and 16S rRNA 
D) initiation factors IF-1,IF-2,and IF-3 
E) all of the above 
A) Shine-Dalgarno sequence 
B) a formylated Met−tRNAfmet 
C) base pairing between the mRNA and 16S rRNA 
D) initiation factors IF-1,IF-2,and IF-3 
E) all of the above

Question 20

Class I and Class II aminoacyl-tRNA synthetases differ in their
(I)structural motifs.
(II)anticodon recognition.
(III)site of aminoacylation.
(IV)amino acid specificity.

Accepted Answer

A) I only 
B) II,III 
C) II,IV 
D) II only 
E) I,II,III,IV 
A) I only 
B) II,III 
C) II,IV 
D) II only 
E) I,II,III,IV

Exam 27: Protein Synthesis

The correct amino acid is covalently attached to a tRNA by the corresponding ______ which is specific for each ______.

The triplet code allows many amino acids to be specified by more than one codon.Such a code is said to be

Matching Choose the correct answer from the list.Not all the answers will be used. -The fidelity of amino acid attachment to a tRNA is enhanced by the ______ ability of the corresponding aaRS.

Proteins are properly folded with the assistance of

Which linkage best describes the covalent bond between an amino acid (AA)and its cognate tRNA?

Which of the following is a function of the ribosome? (I)bind mRNA and allow codon recognition (II)mediate the binding of proteins necessary for initiation,elongation,and termination (III)catalyze synthesis of peptide bonds (IV)translocates such that multiple codons can be read

Which of the following best describes the preparation of fMet-tRNAfmet for translation in prokaryotes?

Matching Choose the correct answer from the list.Not all the answers will be used. -The start codon is usually ______.

Matching Choose the correct answer from the list.Not all the answers will be used. -EF-Tu binds all ______ aminoacyl tRNAs but that of tRNAsec.

Which of the following is(are)used to assist in protein folding? (I)calnexin (II)calreticulin (III)DnaK (IV)GroEL

In E.coli,which of the following factors function to ensure the proper binding of tRNAfMet during mRNA binding and ribosomal subunit assembly? (I)IF-1 (II)IF-2 (III)IF-3 (IV)EF-Ts

Matching Choose the correct answer from the list.Not all the answers will be used. -Translation termination requires ______ that recognize Stop codons.

What happens when a stop codon is reached by a ribosome?

Codons that do not specify amino acids but signal the ribosome to terminate polypeptide chain elongation are termed

Matching Choose the correct answer from the list.Not all the answers will be used. -Some proteins are synthesized as inactive precursors called ______.

Which of following describes proofreading for the addition of amino acids (AAs)to the growing peptide?

The signal recognition particle (SRP)is a _____,and its function is to ______.

The sequence steps involved in elongation of the newly synthesized protein are ordered as follows: (Note: AA=amino acid)

Which of the following is NOT associated with eukaryotic translation initiation?

Class I and Class II aminoacyl-tRNA synthetases differ in their (I)structural motifs. (II)anticodon recognition. (III)site of aminoacylation. (IV)amino acid specificity.

Introduction to the Chemistry of Life

Water

Nucleotides, nucleic Acids, and Genetic Information

Amino Acids

Proteins: Primary Structure

Proteins: Three-Dimensional Structure

Protein Function Part I: Myoglobin and Hemoglobin

Carbohydrates

Lipids and Biological Membranes

Membrane Transport

Enzyme Catalysis

Enzyme Kinetics, inhibition and Control

Biochemical Signaling

Introduction to Metabolism

Glucose Catabolism

Glycogen Metabolism and Gluconeogenesis

Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Mammalian Fuel Metabolism: Integration and Regulation

Nucleotide Metabolism

Nucleic Acid Structure

DNA Replication, repair and Recombination

Transcription and Rna Processing

Regulation of Gene Expression

Filters

The correct amino acid is covalently attached to a tRNA by the corresponding which is specific for each .

Which of the following best describes the preparation of fMet-tRNA_f^met for translation in prokaryotes?

Matching Choose the correct answer from the list.Not all the answers will be used. -EF-Tu binds all ______ aminoacyl tRNAs but that of tRNA^sec.

In E.coli,which of the following factors function to ensure the proper binding of tRNA_f^Metduring mRNA binding and ribosomal subunit assembly? (I)IF-1 (II)IF-2 (III)IF-3 (IV)EF-Ts

The signal recognition particle (SRP)is a _,and its function is to __.