Question 1

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 2

Protein synthesis in prokaryotes always starts with

Accepted Answer

A)  a methionine residue 
B)  a formylmethionine residue 
C)  a cysteine residue 
D)  no specific residue 
A)  a methionine residue 
B)  a formylmethionine residue 
C)  a cysteine residue 
D)  no specific residue

Question 3

The final form of mRNA in eukaryotes has all these features, except:

Accepted Answer

A)  There will be a special nucleotide cap on the 5' end of the mRNA. 
B)  There is usually a poly A tail on the 3' end of the mRNA. 
C)  The mature, active mRNA contains introns. 
D)  Only a single protein is made from any mature mRNA molecule. 
E)  All of these are true. 
A)  There will be a special nucleotide cap on the 5' end of the mRNA. 
B)  There is usually a poly A tail on the 3' end of the mRNA. 
C)  The mature, active mRNA contains introns. 
D)  Only a single protein is made from any mature mRNA molecule. 
E)  All of these are true.

Question 4

Which of the following is not true concerning silent mutations?

Accepted Answer

A)  Silent mutations refer to base sequence differences that do not change the amino acid coded for 
B)  Only changes in base sequence that lead to a different amino acid can have an effect on the organism 
C)  Changes in the sequence of an exonic splicing enhancers can lead faulty removal of introns 
D)  Silent mutations in a gene for pain tolerance has been correlated with human differences in perception of pain 
A)  Silent mutations refer to base sequence differences that do not change the amino acid coded for 
B)  Only changes in base sequence that lead to a different amino acid can have an effect on the organism 
C)  Changes in the sequence of an exonic splicing enhancers can lead faulty removal of introns 
D)  Silent mutations in a gene for pain tolerance has been correlated with human differences in perception of pain

Question 5

A Shine-Dalgarno Sequence is a

Accepted Answer

A)  sequence of nucleotides in the DNA that interacts with the σ-subunit of RNA polymerase to begin transcription. 
B)  sequence of nucleotides in an mRNA that interacts with the small subunit of a ribosome to begin translation. 
C)  sequence of nucleotides in the DNA that interacts with ρ-protein to terminate transcription. 
D)  sequence of nucleotides in an mRNA that functions to terminate translation. 
A)  sequence of nucleotides in the DNA that interacts with the σ-subunit of RNA polymerase to begin transcription. 
B)  sequence of nucleotides in an mRNA that interacts with the small subunit of a ribosome to begin translation. 
C)  sequence of nucleotides in the DNA that interacts with ρ-protein to terminate transcription. 
D)  sequence of nucleotides in an mRNA that functions to terminate translation.

Question 6

The first tRNA (bearing fmet) binds to the

Accepted Answer

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

Question 7

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 8

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

Accepted Answer

A) True 
 B)False

Question 9

The genetic code is said to be degenerate. This means that

Accepted Answer

A)  each codon codes for more than one amino acid. 
B)  each anticodon can interact with many different triplet sequences in the mRNA, which may differ in any or all of the three nucleotides. 
C)  many of the amino acids are coded for by different codons. 
D)  the code is universally used by virtually all species. 
A)  each codon codes for more than one amino acid. 
B)  each anticodon can interact with many different triplet sequences in the mRNA, which may differ in any or all of the three nucleotides. 
C)  many of the amino acids are coded for by different codons. 
D)  the code is universally used by virtually all species.

Question 10

How do eukaryotic and prokaryotic translation compare?

Accepted Answer

A)  There is little to no difference between them; all the factors are homologous. 
B)  Eukaryotes utilize very different protein factors during the process but the ribosomes are homologous. 
C)  Eukaryotic ribosomes are very different, but the protein factors used during the process are homologous. 
D)  Both eukaryotic ribosomes and the protein factors used during the process are very different. 
A)  There is little to no difference between them; all the factors are homologous. 
B)  Eukaryotes utilize very different protein factors during the process but the ribosomes are homologous. 
C)  Eukaryotic ribosomes are very different, but the protein factors used during the process are homologous. 
D)  Both eukaryotic ribosomes and the protein factors used during the process are very different.

Question 11

In protein synthesis formation of new peptide bonds is catalyzed by

Accepted Answer

A)  elongation factor EF−Tu 
B)  elongation factor EF−Ts 
C)  elongation factor EF−G 
D)  peptidyl transferase 
A)  elongation factor EF−Tu 
B)  elongation factor EF−Ts 
C)  elongation factor EF−G 
D)  peptidyl transferase

Question 12

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

Question 13

Leader sequences for protein transport to specific organelles are removed by proteases associated with the:

Accepted Answer

A)  endoplasmic reticulum 
B)  golgi apparatus 
C)  nucleus 
D)  mitochondra 
E)  none of these 
A)  endoplasmic reticulum 
B)  golgi apparatus 
C)  nucleus 
D)  mitochondra 
E)  none of these

Question 14

The standard free energy change for the following reaction is about zero. amino acid + ATP + tRNA → aminoacyl-tRNA + AMP + PPi??The driving force for this reaction in the cell is

Accepted Answer

A)  the relatively low concentrations of the reactants 
B)  the subsequent reaction of peptide bond formation, which is energetically favorable 
C)  the subsequent hydrolysis of pyrophosphate, which releases energy 
D)  the increased resonance stability of the acyl group on aminoacyl-tRNA 
A)  the relatively low concentrations of the reactants 
B)  the subsequent reaction of peptide bond formation, which is energetically favorable 
C)  the subsequent hydrolysis of pyrophosphate, which releases energy 
D)  the increased resonance stability of the acyl group on aminoacyl-tRNA

Question 15

Using the genetic code, indicate which polypeptides would be synthesized if poly (UGG) were used as a synthetic mRNA?

Accepted Answer

A)  poly(gly) 
B)  poly(trp) 
C)  poly(trp-val-gly) 
D)  poly(trp), poly(val), poly(gly) 
A)  poly(gly) 
B)  poly(trp) 
C)  poly(trp-val-gly) 
D)  poly(trp), poly(val), poly(gly)

Question 16

The activating enzymes can actually remove wrong amino acids attached to a tRNA.

Accepted Answer

A) True 
 B)False

Question 17

The formylation of methionine in prokaryotes

Accepted Answer

A)  depends on two different tRNAs, where methionine can be formylated when bound to one form and not the other. 
B)  depends on two different tRNAs, where methionine can be formylated when bound to either one. 
C)  depends on one tRNA, where methionine is formylated after binding. 
D)  takes place before methionine is bound to tRNA. 
A)  depends on two different tRNAs, where methionine can be formylated when bound to one form and not the other. 
B)  depends on two different tRNAs, where methionine can be formylated when bound to either one. 
C)  depends on one tRNA, where methionine is formylated after binding. 
D)  takes place before methionine is bound to tRNA.

Question 18

An aminoacyl-tRNA is initially bound to the ribosome

Accepted Answer

A)  at the A site on the 50S subunit 
B)  at the P site on the 50S subunit 
C)  at the A site on the 30S subunit 
D)  at the P site on the 30S subunit 
A)  at the A site on the 50S subunit 
B)  at the P site on the 50S subunit 
C)  at the A site on the 30S subunit 
D)  at the P site on the 30S subunit

Question 19

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 20

In bacteria, translation of the mRNA begins

Accepted Answer

A)  during the synthesis of the mRNA. 
B)  after synthesis of the mRNA has been completed. 
C)  after 5' capping of the mRNA. 
D)  after all processing (capping, polyadenylation, and removal of introns) has taken place. 
A)  during the synthesis of the mRNA. 
B)  after synthesis of the mRNA has been completed. 
C)  after 5' capping of the mRNA. 
D)  after all processing (capping, polyadenylation, and removal of introns) has taken place.

Exam 12: Protein Synthesis: Translation of the Genetic Message

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

Protein synthesis in prokaryotes always starts with

The final form of mRNA in eukaryotes has all these features, except:

Which of the following is not true concerning silent mutations?

A Shine-Dalgarno Sequence is a

The first tRNA (bearing fmet) binds to the

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

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

The genetic code is said to be degenerate. This means that

How do eukaryotic and prokaryotic translation compare?

In protein synthesis formation of new peptide bonds is catalyzed by

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

Leader sequences for protein transport to specific organelles are removed by proteases associated with the:

The standard free energy change for the following reaction is about zero. amino acid + ATP + tRNA → aminoacyl-tRNA + AMP + PPi??The driving force for this reaction in the cell is

Using the genetic code, indicate which polypeptides would be synthesized if poly (UGG) were used as a synthetic mRNA?

The activating enzymes can actually remove wrong amino acids attached to a tRNA.

The formylation of methionine in prokaryotes

An aminoacyl-tRNA is initially bound to the ribosome

The template for protein synthesis is:

In bacteria, translation of the mRNA begins

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

The standard free energy change for the following reaction is about zero. amino acid + ATP + tRNA → aminoacyl-tRNA + AMP + PP_i_??The driving force for this reaction in the cell is