Question 1

What is the function of the release factor during translation in eukaryotes?

Accepted Answer

A)  It binds to the stop codon in the A site in place of a tRNA. 
B)  It releases the amino acid from its tRNA to allow the amino acid to form a peptide bond. 
C)  It supplies a source of energy for termination of translation. 
D)  It releases the ribosome from the ER to allow polypeptides into the cytosol. 
A)  It binds to the stop codon in the A site in place of a tRNA. 
B)  It releases the amino acid from its tRNA to allow the amino acid to form a peptide bond. 
C)  It supplies a source of energy for termination of translation. 
D)  It releases the ribosome from the ER to allow polypeptides into the cytosol.

Question 2

Which of the following processes occurs in eukaryotic gene expression?

Accepted Answer

A)  mRNA, tRNA, and rRNA are translated. 
B)  RNA polymerase binds to the terminator sequence. 
C)  A cap is added to the 5′ end of the mRNA. 
D)  RNA polymerase requires tRNA to elongate the molecule. 
A)  mRNA, tRNA, and rRNA are translated. 
B)  RNA polymerase binds to the terminator sequence. 
C)  A cap is added to the 5′ end of the mRNA. 
D)  RNA polymerase requires tRNA to elongate the molecule.

Question 3

Which of the following DNA mutations is most likely to damage the protein it specifies?

Accepted Answer

A)  a base-pair deletion 
B)  an addition of three nucleotides 
C)  a substitution in the last base of a codon 
D)  a codon deletion 
A)  a base-pair deletion 
B)  an addition of three nucleotides 
C)  a substitution in the last base of a codon 
D)  a codon deletion

Question 4

Which component is not directly involved in translation?

Accepted Answer

A)  GTP 
B)  DNA 
C)  tRNA 
D)  ribosomes 
A)  GTP 
B)  DNA 
C)  tRNA 
D)  ribosomes

Question 5

Which of the following statements correctly describes the effect a nonsense mutation would have on a gene?

Accepted Answer

A)  It changes an amino acid in the encoded protein. 
B)  It has no effect on the amino acid sequence of the encoded protein. 
C)  It introduces a premature stop codon into the mRNA. 
D)  It alters the reading frame of the mRNA. 
A)  It changes an amino acid in the encoded protein. 
B)  It has no effect on the amino acid sequence of the encoded protein. 
C)  It introduces a premature stop codon into the mRNA. 
D)  It alters the reading frame of the mRNA.

Question 6

Which of the following types of mutation, resulting in an error in the mRNA just after the AUG start of translation, is likely to have the most serious effect on the polypeptide product?

Accepted Answer

A)  a deletion of a codon 
B)  a deletion of two nucleotides 
C)  a substitution of the third nucleotide in an ACC codon 
D)  a substitution of the first nucleotide of a GGG codon 
A)  a deletion of a codon 
B)  a deletion of two nucleotides 
C)  a substitution of the third nucleotide in an ACC codon 
D)  a substitution of the first nucleotide of a GGG codon

Question 7

Which of the following processes occurs during transcription?

Accepted Answer

A)  DNA is replicated 
B)  RNA is synthesised 
C)  proteins are synthesised 
D)  mRNA attaches to ribosomes 
A)  DNA is replicated 
B)  RNA is synthesised 
C)  proteins are synthesised 
D)  mRNA attaches to ribosomes

Question 8

In the structural organisation of many eukaryotic genes, individual exons may be related to which of the following?

Accepted Answer

A)  the sequence of the intron that immediately precedes each exon 
B)  the number of polypeptides making up the functional protein 
C)  the various domains of the polypeptide product 
D)  the number of start sites for transcription 
A)  the sequence of the intron that immediately precedes each exon 
B)  the number of polypeptides making up the functional protein 
C)  the various domains of the polypeptide product 
D)  the number of start sites for transcription

Question 9

Which of the following statements supports the one gene-one enzyme hypothesis?

Accepted Answer

A)  A mutation in a single gene can result in a defective protein. 
B)  Alkaptonuria results when individuals lack multiple enzymes involved in the catalysis of homogentisic acid. 
C)  Sickle-cell anaemia results in normal haemoglobin. 
D)  Multiple antibody genes can code for different related proteins, depending on the splicing that takes place post-transcriptionally. 
A)  A mutation in a single gene can result in a defective protein. 
B)  Alkaptonuria results when individuals lack multiple enzymes involved in the catalysis of homogentisic acid. 
C)  Sickle-cell anaemia results in normal haemoglobin. 
D)  Multiple antibody genes can code for different related proteins, depending on the splicing that takes place post-transcriptionally.

Question 10

How does the primary transcript in the nucleus of a eukaryotic cell compare to the functional mRNA?

Accepted Answer

A)  the primary transcript is the same size as the mRNA 
B)  the primary transcript is larger than the mRNA 
C)  the primary transcript is smaller than the mRNA 
D)  both the primary transcript and mRNA contain introns 
A)  the primary transcript is the same size as the mRNA 
B)  the primary transcript is larger than the mRNA 
C)  the primary transcript is smaller than the mRNA 
D)  both the primary transcript and mRNA contain introns

Question 11

Which of the following molecules are required for the process of translation?

Accepted Answer

A)  mRNA, tRNA, DNA, and rRNA 
B)  mRNA, DNA, and rRNA 
C)  mRNA, tRNA, and rRNA 
D)  mRNA, tRNA, and DNA 
A)  mRNA, tRNA, DNA, and rRNA 
B)  mRNA, DNA, and rRNA 
C)  mRNA, tRNA, and rRNA 
D)  mRNA, tRNA, and DNA

Question 12

- Which of the following sequences of nucleotides are possible in the template strand of DNA that would code for the polypeptide sequence Phe-Leu-Ile-Val?

Accepted Answer

A)  5′-TTG-CTA-CAG-TAG-3′ 
B)  5′-AUG-CTG-CAG-TAT-3′ 
C)  3′-AAA-AAT-ATA-ACA-5′ 
D)  3′-AAA-GAA-TAA-CAA-5′ 
A)  5′-TTG-CTA-CAG-TAG-3′ 
B)  5′-AUG-CTG-CAG-TAT-3′ 
C)  3′-AAA-AAT-ATA-ACA-5′ 
D)  3′-AAA-GAA-TAA-CAA-5′

Question 13

A part of an mRNA molecule with the following sequence is being read by a ribosome: 5′-CCG-ACG-3′ (mRNA). The following charged transfer RNA molecules (with their anticodons shown in the 3′ to 5′ direction) are available. Two of them can correctly match the mRNA so that a dipeptide can form.
$$\begin{array} { | c | c | } 
\hline \text { tRNA Anticodon } & \text { Amino Acid } \
\hline \text { GGC } & \text { Proline } \
\text { CGU } & \text { Alanine } \
\text { UGC } & \text { Threonine } \
\text { CCG } & \text { Glycine } \
\text { ACG } & \text { Cysteine } \
\text { CGG } & \text { Alanine } \
\hline
\end{array}$$
-
Which of the following dipeptides will form from this mRNA?

Accepted Answer

A)  cysteine-alanine 
B)  proline-threonine 
C)  glycine-cysteine 
D)  alanine-alanine 
A)  cysteine-alanine 
B)  proline-threonine 
C)  glycine-cysteine 
D)  alanine-alanine

Question 14

- Refer to the figure. Which of the triplets below is a possible anticodon for a tRNA that transports proline to a ribosome?

Accepted Answer

A)  3′-UUC-5′ 
B)  3′-CCG-5′ 
C)  3′-GGC-5′ 
D)  3′-CCC-5′ 
A)  3′-UUC-5′ 
B)  3′-CCG-5′ 
C)  3′-GGC-5′ 
D)  3′-CCC-5′

Question 15

The figure shows a simple metabolic pathway. 
-If A, B, and C are all required for growth, a strain that is mutant for the gene-encoding enzyme A would be able to grow on medium supplemented with which of the following nutrient(s)?

Accepted Answer

A)  nutrient A only 
B)  either nutrient B or C 
C)  nutrient C only 
D)  nutrients A and C 
A)  nutrient A only 
B)  either nutrient B or C 
C)  nutrient C only 
D)  nutrients A and C

Question 16

Codons are three-base sequences in mRNA that specify the addition of a single amino acid to the growing protein chain during translation. How do eukaryotic codons and prokaryotic codons compare?

Accepted Answer

A)  Prokaryotic codons usually contain different bases than those of eukaryotes. 
B)  Prokaryotic codons usually specify different amino acids than those of eukaryotes. 
C)  The translation of codons is mediated by tRNAs in eukaryotes, but translation requires no intermediate molecules such as tRNAs in prokaryotes. 
D)  Codons are a nearly universal language among all organisms. 
A)  Prokaryotic codons usually contain different bases than those of eukaryotes. 
B)  Prokaryotic codons usually specify different amino acids than those of eukaryotes. 
C)  The translation of codons is mediated by tRNAs in eukaryotes, but translation requires no intermediate molecules such as tRNAs in prokaryotes. 
D)  Codons are a nearly universal language among all organisms.

Question 17

E = exon and I = intron
5′-UTR E1 I1 E2 I2 E3 I3 E4 UTR-3′
Which components of the previous molecule will also be found in mRNA in the cytosol?

Accepted Answer

A)  5′-UTR I1 I2 I3 UTR-3′ 
B)  5′-E1 E2 E3 E4-3′ 
C)  5′-UTR E1 E2 E3 E4 UTR-3′ 
D)  5′-E1 I1 E2 I2 E3 I3 E4-3′ 
A)  5′-UTR I1 I2 I3 UTR-3′ 
B)  5′-E1 E2 E3 E4-3′ 
C)  5′-UTR E1 E2 E3 E4 UTR-3′ 
D)  5′-E1 I1 E2 I2 E3 I3 E4-3′

Question 18

Which one of the following structures, if missing, would usually prevent translation from starting?

Accepted Answer

A)  exon 
B)  5′ cap 
C)  AUG codon 
D)  poly-A tail 
A)  exon 
B)  5′ cap 
C)  AUG codon 
D)  poly-A tail

Question 19

Which of the following mutations would be most likely to have a harmful effect on an organism?

Accepted Answer

A)  a deletion of three nucleotides near the middle of a gene 
B)  a single nucleotide deletion in the middle of an intron 
C)  a single nucleotide deletion near the end of the coding sequence 
D)  a single nucleotide insertion downstream of, and close to, the start of the coding sequence 
A)  a deletion of three nucleotides near the middle of a gene 
B)  a single nucleotide deletion in the middle of an intron 
C)  a single nucleotide deletion near the end of the coding sequence 
D)  a single nucleotide insertion downstream of, and close to, the start of the coding sequence

Question 20

Use the figure to identify a 5′ → 3′ sequence of nucleotides in the DNA template strand for an mRNA coding for the polypeptide sequence Phe-Pro-Lys.

Accepted Answer

A)  5-UUUCCCAAA-3 
B)  5-GAACCCCTT-3 
C)  5-CTTCGGGAA-3 
D)  5-AAACCCUUU-3 
A)  5-UUUCCCAAA-3 
B)  5-GAACCCCTT-3 
C)  5-CTTCGGGAA-3 
D)  5-AAACCCUUU-3

Exam 17: Gene Expression: From Gene to Protein

What is the function of the release factor during translation in eukaryotes?

Which of the following processes occurs in eukaryotic gene expression?

Which of the following DNA mutations is most likely to damage the protein it specifies?

Which component is not directly involved in translation?

Which of the following statements correctly describes the effect a nonsense mutation would have on a gene?

Which of the following types of mutation, resulting in an error in the mRNA just after the AUG start of translation, is likely to have the most serious effect on the polypeptide product?

Which of the following processes occurs during transcription?

In the structural organisation of many eukaryotic genes, individual exons may be related to which of the following?

Which of the following statements supports the one gene-one enzyme hypothesis?

How does the primary transcript in the nucleus of a eukaryotic cell compare to the functional mRNA?

Which of the following molecules are required for the process of translation?

- Which of the following sequences of nucleotides are possible in the template strand of DNA that would code for the polypeptide sequence Phe-Leu-Ile-Val?

- Refer to the figure. Which of the triplets below is a possible anticodon for a tRNA that transports proline to a ribosome?

The figure shows a simple metabolic pathway. -If A, B, and C are all required for growth, a strain that is mutant for the gene-encoding enzyme A would be able to grow on medium supplemented with which of the following nutrient(s)?

Codons are three-base sequences in mRNA that specify the addition of a single amino acid to the growing protein chain during translation. How do eukaryotic codons and prokaryotic codons compare?

E = exon and I = intron 5′-UTR E1 I1 E2 I2 E3 I3 E4 UTR-3′ Which components of the previous molecule will also be found in mRNA in the cytosol?

Which one of the following structures, if missing, would usually prevent translation from starting?

Which of the following mutations would be most likely to have a harmful effect on an organism?

Use the figure to identify a 5′ → 3′ sequence of nucleotides in the DNA template strand for an mRNA coding for the polypeptide sequence Phe-Pro-Lys.

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Regulation of Gene Expression

Viruses

Dna Tools and Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonised Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Vascular Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signalling

Nervous Systems

Sensory and Motor Mechanisms

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