Question 1

As in RNA and DNA synthesis, the synthesis of proteins follows the following steps, except:

Accepted Answer

A)   Activation of monomers
B)   Initiation
C)   Elongation
D)   Termination
E)   All of these are involved in all polymer synthesisF) A) and B)
G) All of the above

Question 2

Which of the following is not an advantage of degeneracy in the genetic code?

Accepted Answer

A)   More than one amino acid can bind to a tRNA.
B)   Each tRNA can bind to more than one codon.
C)   Most codons can bind to more than one tRNA.
D)   Fewer tRNA molecules are needed.E) B) and D)
F) B) and C)

Question 3

Which of the following is not true?

Accepted Answer

A)   A single activating enzyme can interact with all the tRNAs for its corresponding amino acid
B)   The selectivity of the aminoacyl-tRNA synthetases for their tRNA molecules is often called the second genetic code
C)   There are two major classes of aminoacyl-tRNA synthetases
D)   aminoacyl-tRNA synthetases link amino acids to tRNA molecules without the need for an energy sourceE) C) and D)
F) A) and C)

Question 4

It was recently discovered that AUG is not always the start codon in which of the following systems?

Accepted Answer

A)   viruses
B)   mammalian immune system proteins
C)   mitochondria
D)   all of theseE) A) and B)
F) A) and C)

Question 5

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 trueE) A) and B)
F) A) and C)

Question 6

The amino acids are initially attached to either the 2' or 3' hydroxyl group of the tRNA.

Accepted Answer

A) True 
 B)False

Question 7

Activation of amino acids always takes place

Accepted Answer

A)   on the ribosomes
B)   on a ribosomal subunit
C)   on the rough endoplasmic reticulum
D)   in the cytoplasmE) A) and B)
F) All of the above

Question 8

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

Accepted Answer

A)   Keep the ribosomal subunits bound together.
B)   Lead the incoming tRNA to its correct position on the ribosome.
C)   Carry GTP to provide energy for certain steps in the elongation process.
D)   Regenerate the elongation factors by replacing GTP for GDP.
E)   The elongation factors do all of these.F) A) and D)
G) C) and D)

Question 9

Which of the following is necessary for chain termination in protein synthesis?

Accepted Answer

A)   termination codons of mRNA
B)   release factors
C)   GTP
D)   all of these
E)   none of theseF) B) and C)
G) C) and D)

Question 10

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

Accepted Answer

A) True 
 B)False

Question 11

Aminoacyl-tRNA Synthetases are involved in which step of translation?

Accepted Answer

A)   activation
B)   initiation
C)   elongation
D)   termination
E)   none of theseF) D) and E)
G) A) and D)

Question 12

A polysome is

Accepted Answer

A)   a complex consisting of one mRNA to which several ribosomes are attached
B)   a polypeptide chain in the process of being formed
C)   an intermediate stage in the self-assembly of ribosomes
D)   an aggregate of ribosomal proteinsE) A) and C)
F) None of the above

Question 13

How do eukaryotic ribosomes prevent false starts at inappropriate parts of the mRNA?

Accepted Answer

A)   There is a consensus sequence, called the Kozak sequence, surrounding the start codon in eukaryotes.
B)   The Shine-Dalgarno sequence positions the ribosome properly, just as in prokaryotes.
C)   Only one start codon ever appears in eukaryotic mRNA, so false starts are not a problem.
D)   Nothing; false starts are quite common in eukaryotic translation.E) A) and C)
F) B) and C)

Question 14

N-formyl methionine

Accepted Answer

A)   can be found attached to every protein in E. coli.
B)   can be found attached to some proteins in E. coli.
C)   is never found on proteins in E. coli.D) A) and B)
E) All of the above

Question 15

Under certain conditions, tRNAs can bind to the standard stop codons.

Accepted Answer

A) True 
 B)False

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.E) A) and B)
F) None of the above

Question 17

Which of the following statements concerning tRNAs is false?

Accepted Answer

A)   They have distinctive cloverleaf tertiary structures
B)   They are unique in that they are transcribed by DNA polymerases
C)   They contain many modified nucleobases
D)   They contain the anticodon sequenceE) C) and D)
F) A) and B)

Question 18

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

Accepted Answer

A)   Cause the ribosomal subunits to dissociate.
B)   Bind to the stop codons on the mRNA.
C)   Carry GTP to provide energy for certain steps in the termination process.
D)   Release the new peptide from the ribosome.
E)   The termination factors do all of these.F) None of the above
G) A) and C)

Question 19

The mRNA must contain the following to allow for initiation of protein synthesis in E. coli.

Accepted Answer

A)   A purine rich sequence to bind to the ribosome.
B)   A pyrimidine rich sequence to bind to the ribosome.
C)   A Shine-Delgarno sequence.
D)   A purine rich sequence to bind to the ribosome and a Shine-Delgarno sequence.
E)   A pyrimidine rich sequence to bind to the ribosome and a Shine-Delgarno sequence.F) B) and E)
G) A) and B)

Question 20

Wobble allows each codon to interact with more than one tRNA.

Accepted Answer

A) True 
 B)False

Exam 12: Protein Synthesis: Translation of the Genetic Message

The amino acids are initially attached to either the 2' or 3' hydroxyl group of the tRNA.

Correct AnswerverifiedShow Answer

Which of the following is not true?

Correct AnswerverifiedShow Answer

A polysome is

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Wobble allows each codon to interact with more than one tRNA.

Correct AnswerverifiedShow Answer

The mRNA must contain the following to allow for initiation of protein synthesis in E. coli.

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Which of the following statements concerning tRNAs is false?

Correct AnswerverifiedShow Answer

Activation of amino acids always takes place

Correct AnswerverifiedShow Answer

It was recently discovered that AUG is not always the start codon in which of the following systems?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Which of the following is necessary for chain termination in protein synthesis?

Correct AnswerverifiedShow Answer

Aminoacyl-tRNA Synthetases are involved in which step of translation?

Correct AnswerverifiedShow Answer

N-formyl methionine

Correct AnswerverifiedShow Answer

How do eukaryotic ribosomes prevent false starts at inappropriate parts of the mRNA?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Under certain conditions, tRNAs can bind to the standard stop codons.

Correct AnswerverifiedShow Answer

As in RNA and DNA synthesis, the synthesis of proteins follows the following steps, except:

Correct AnswerverifiedShow Answer

Which of the following is not an advantage of degeneracy in the genetic code?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified