Question 1

Each tRNA molecule has a separate activating enzyme.

Accepted Answer

A) True 
 B)False

Question 2

The match between codon and anticodon is one of the many proofreading aspects of protein synthesis.

Accepted Answer

A) True 
 B)False

Question 3

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 4

Specificity of aminoacyl-tRNA synthetases is always based on the anticodon.

Accepted Answer

A) True 
 B)False

Question 5

Wobble allows a single codon to code for more than one amino acid.

Accepted Answer

A) True 
 B)False

Question 6

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 7

The actual functions of the factors in eukaryotes are similar to the functions of these factors in bacteria.

Accepted Answer

A) True 
 B)False

Question 8

At which position on tRNA is the wobble base of the triplet anticodon?

Accepted Answer

A)  1st position (5' letter) 
B)  2nd position 
C)  3rd position (3' letter) 
D)  Wobble can occur at any position. 
A)  1st position (5' letter) 
B)  2nd position 
C)  3rd position (3' letter) 
D)  Wobble can occur at any position.

Question 9

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

Question 10

Amino acids linked to the 2'-end of a tRNA

Accepted Answer

A)  are regular substrates for protein synthesis. 
B)  are transferred to the 3' position prior to their use in protein synthesis. 
C)  are prompted hydrolysed off as part of a proofreading mechanism. 
D)  never occur. 
A)  are regular substrates for protein synthesis. 
B)  are transferred to the 3' position prior to their use in protein synthesis. 
C)  are prompted hydrolysed off as part of a proofreading mechanism. 
D)  never occur.

Question 11

What type of assay using tRNAs and ribosomes enabled complete determination of the genetic code?

Accepted Answer

A)  filter binding assays 
B)  high performance chromatography 
C)  electrophoresis 
D)  density gradient centrifugation 
A)  filter binding assays 
B)  high performance chromatography 
C)  electrophoresis 
D)  density gradient centrifugation

Question 12

Which of the following is true concerning protein synthesis and memory?

Accepted Answer

A)  Animals that cannot make new proteins have no memories 
B)  Inhibition of protein synthesis in eukaryotes leads to lack of long term memory 
C)  Production of CREB is inhibited when strong memories are made 
D)  none of these is true 
A)  Animals that cannot make new proteins have no memories 
B)  Inhibition of protein synthesis in eukaryotes leads to lack of long term memory 
C)  Production of CREB is inhibited when strong memories are made 
D)  none of these is true

Question 13

There is no codon for the amino acid hydroxyproline,but this amino acid is a prominent feature of collagen structure.Which of the following is a likely explanation?

Accepted Answer

A)  Hydroxyproline is substituted for proline after translation by a cut and patch mechanism. 
B)  Proline is covalently modified to give hydroxyproline after translation. 
C)  There is an alternative mechanism for synthesis of proteins that contain hydroxyproline. 
D)  It is not possible to form a hypothesis from the information given. 
A)  Hydroxyproline is substituted for proline after translation by a cut and patch mechanism. 
B)  Proline is covalently modified to give hydroxyproline after translation. 
C)  There is an alternative mechanism for synthesis of proteins that contain hydroxyproline. 
D)  It is not possible to form a hypothesis from the information given.

Question 14

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 15

Which amino acids have unique codons?

Accepted Answer

A)  met, gly 
B)  trp, met 
C)  tyr, met 
D)  stop, his 
A)  met, gly 
B)  trp, met 
C)  tyr, met 
D)  stop, his

Question 16

Which of the following statements concerning the genetic code is false?

Accepted Answer

A)  It is based on triplets. 
B)  It is non-overlapping. 
C)  Commas are used. 
D)  It is degenerate. 
A)  It is based on triplets. 
B)  It is non-overlapping. 
C)  Commas are used. 
D)  It is degenerate.

Question 17

What is the mode of action of puromycin in the inhibition of protein synthesis?

Accepted Answer

A)  inhibition of peptidyl transferase 
B)  inactivation of EF-G 
C)  termination of the growing polypeptide chain 
D)  dissociation of mRNA from the ribosome 
A)  inhibition of peptidyl transferase 
B)  inactivation of EF-G 
C)  termination of the growing polypeptide chain 
D)  dissociation of mRNA from the ribosome

Question 18

The template for protein synthesis is:

Accepted Answer

A)  a mRNA strand 
B)  the DNA coding strand 
C)  the DNA template strand 
D)  a protein primer 
E)  none of these 
A)  a mRNA strand 
B)  the DNA coding strand 
C)  the DNA template strand 
D)  a protein primer 
E)  none of these

Question 19

How many codons are possible in a system in which a sequence of three bases specifies a single amino acid?

Accepted Answer

A)  20 
B)  24 
C)  27 
D)  64 
A)  20 
B)  24 
C)  27 
D)  64

Question 20

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

Exam 12: Protein Synthesis: Translation of the Genetic Message

Each tRNA molecule has a separate activating enzyme.

The match between codon and anticodon is one of the many proofreading aspects of protein synthesis.

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

Specificity of aminoacyl-tRNA synthetases is always based on the anticodon.

Wobble allows a single codon to code for more than one amino acid.

How many codons are known for each amino acid?

The actual functions of the factors in eukaryotes are similar to the functions of these factors in bacteria.

At which position on tRNA is the wobble base of the triplet anticodon?

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

Amino acids linked to the 2'-end of a tRNA

What type of assay using tRNAs and ribosomes enabled complete determination of the genetic code?

Which of the following is true concerning protein synthesis and memory?

There is no codon for the amino acid hydroxyproline,but this amino acid is a prominent feature of collagen structure.Which of the following is a likely explanation?

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

Which amino acids have unique codons?

Which of the following statements concerning the genetic code is false?

What is the mode of action of puromycin in the inhibition of protein synthesis?

The template for protein synthesis is:

How many codons are possible in a system in which a sequence of three bases specifies a single amino acid?

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

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

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