Question 1

Which of the following processes occurs when termination of translation takes place?

Accepted Answer

A)  The end of the mRNA molecule is reached. 
B)  A stop codon is reached. 
C)  The 5′ cap is reached. 
D)  The poly-A tail is reached. 
A)  The end of the mRNA molecule is reached. 
B)  A stop codon is reached. 
C)  The 5′ cap is reached. 
D)  The poly-A tail is reached.

Question 2

Use the figure to answer the question.
 
The figure represents tRNA that recognizes and binds a particular amino acid (in this instance, phenylalanine). Which codon on the mRNA strand codes for this amino acid?

Accepted Answer

A)  5′-UGG-3′ 
B)  3′-GUG-5′ 
C)  5′-GUA-3′ 
D)  5′-UUC-3′ 
A)  5′-UGG-3′ 
B)  3′-GUG-5′ 
C)  5′-GUA-3′ 
D)  5′-UUC-3′

Question 3

A single base substitution mutation is likely to have a less deleterious effect when the base change exhibits which of the following results?

Accepted Answer

A)  a stop codon 
B)  a codon that specifies the same amino acid as the original codon 
C)  an amino acid substitution that alters the tertiary structure of the protein 
D)  an amino acid substitution at the active site of an enzyme 
A)  a stop codon 
B)  a codon that specifies the same amino acid as the original codon 
C)  an amino acid substitution that alters the tertiary structure of the protein 
D)  an amino acid substitution at the active site of an enzyme

Question 4

The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single codon. What is the result of this type of mutation?

Accepted Answer

A)  a base-pair substitution 
B)  a frameshift mutation 
C)  a polypeptide missing an amino acid 
D)  a nonsense mutation 
A)  a base-pair substitution 
B)  a frameshift mutation 
C)  a polypeptide missing an amino acid 
D)  a nonsense mutation

Question 5

Use the figure to answer the question.
 
What type of bonding is responsible for maintaining the shape of the tRNA molecule shown in the figure?

Accepted Answer

A)  ionic bonding between phosphates 
B)  hydrogen bonding between base pairs 
C)  van der Waals interactions between hydrogen atoms 
D)  peptide bonding between amino acids 
A)  ionic bonding between phosphates 
B)  hydrogen bonding between base pairs 
C)  van der Waals interactions between hydrogen atoms 
D)  peptide bonding between amino acids

Question 6

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 7

Which of the following properties is associated with a protein that will be secreted from a eukaryotic cell?

Accepted Answer

A)  It must be translated by a ribosome that remains free within the cytosol. 
B)  Its signal sequence must target it to the ER, after which it goes to the Golgi. 
C)  Its signal sequence must be cleaved off before the polypeptide can enter the ER. 
D)  Its signal sequence must target it to the plasma membrane, where it causes exocytosis. 
A)  It must be translated by a ribosome that remains free within the cytosol. 
B)  Its signal sequence must target it to the ER, after which it goes to the Golgi. 
C)  Its signal sequence must be cleaved off before the polypeptide can enter the ER. 
D)  Its signal sequence must target it to the plasma membrane, where it causes exocytosis.

Question 8

Which of the following statements correctly describes Archibald Garrod's hypothesis for how "inborn errors of metabolism" such as alkaptonuria occur?

Accepted Answer

A)  Metabolic enzymes require vitamin cofactors, and affected individuals have significant nutritional deficiencies. 
B)  Enzymes are made of DNA, and affected individuals lack DNA polymerase. 
C)  Certain metabolic reactions are carried out by ribozymes, and affected individuals lack key splicing factors. 
D)  Genes dictate the production of specific enzymes, and affected individuals have genetic defects that cause them to lack certain enzymes. 
A)  Metabolic enzymes require vitamin cofactors, and affected individuals have significant nutritional deficiencies. 
B)  Enzymes are made of DNA, and affected individuals lack DNA polymerase. 
C)  Certain metabolic reactions are carried out by ribozymes, and affected individuals lack key splicing factors. 
D)  Genes dictate the production of specific enzymes, and affected individuals have genetic defects that cause them to lack certain enzymes.

Question 9

Use the following information to answer the question.
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 anticodons in the first tRNA to bind will complement this mRNA?

Accepted Answer

A)  3?-GGC-5? 
B)  5?-GGC-3? 
C)  5?-UGC-3? 
D)  3?-UGC-5? 
A)  3?-GGC-5? 
B)  5?-GGC-3? 
C)  5?-UGC-3? 
D)  3?-UGC-5?

Question 10

Which of the following statements correctly describes a ribozyme?

Accepted Answer

A)  It is a catalyst that uses RNA as a substrate. 
B)  It is an RNA with catalytic activity. 
C)  It is an enzyme that catalyzes the association between the large and small ribosomal subunits. 
D)  It is an enzyme that synthesizes RNA as part of the transcription process. 
A)  It is a catalyst that uses RNA as a substrate. 
B)  It is an RNA with catalytic activity. 
C)  It is an enzyme that catalyzes the association between the large and small ribosomal subunits. 
D)  It is an enzyme that synthesizes RNA as part of the transcription process.

Question 11

Post-translational modifications of proteins may include which of the following processes?

Accepted Answer

A)  removal of introns 
B)  addition of a 5′ cap 
C)  addition of a poly-A tail 
D)  addition of carbohydrates to form a glycoprotein 
A)  removal of introns 
B)  addition of a 5′ cap 
C)  addition of a poly-A tail 
D)  addition of carbohydrates to form a glycoprotein

Question 12

Which of the following processes occurs during transcription?

Accepted Answer

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

Question 13

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 anemia results in normal hemoglobin. 
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 anemia results in normal hemoglobin. 
D)  Multiple antibody genes can code for different related proteins, depending on the splicing that takes place post-transcriptionally.

Question 14

Which of the following is not true of RNA processing?

Accepted Answer

A)  Exons are cut out before mRNA leaves the nucleus. 
B)  Nucleotides may be added at both ends of the RNA. 
C)  Ribozymes may function in RNA splicing. 
D)  RNA splicing can be catalyzed by spliceosomes. 
A)  Exons are cut out before mRNA leaves the nucleus. 
B)  Nucleotides may be added at both ends of the RNA. 
C)  Ribozymes may function in RNA splicing. 
D)  RNA splicing can be catalyzed by spliceosomes.

Question 15

The following question refers to this table of codons.
 
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 16

Once researchers identified DNA as the molecule responsible for transmitting heritable traits, they asked how information was transferred from the DNA in the nucleus to the site of protein synthesis in the cytoplasm. Which of the following statements correctly describes the mechanism of information transfer in eukaryotes that accomplishes this task?

Accepted Answer

A)  DNA from a single gene is replicated and transferred to the cytoplasm, where it serves as a template for protein synthesis. 
B)  Messenger RNA is transcribed from a single gene and transfers information from the DNA in the nucleus to the cytoplasm, where protein synthesis takes place. 
C)  Histone proteins in the chromosomes transfer information from the nucleus to the ribosome, where protein synthesis takes place. 
D)  Transfer RNA takes information from DNA directly to a ribosome, where protein synthesis takes place. 
A)  DNA from a single gene is replicated and transferred to the cytoplasm, where it serves as a template for protein synthesis. 
B)  Messenger RNA is transcribed from a single gene and transfers information from the DNA in the nucleus to the cytoplasm, where protein synthesis takes place. 
C)  Histone proteins in the chromosomes transfer information from the nucleus to the ribosome, where protein synthesis takes place. 
D)  Transfer RNA takes information from DNA directly to a ribosome, where protein synthesis takes place.

Question 17

Transcription in eukaryotes requires which of the following molecules in addition to RNA polymerase?

Accepted Answer

A)  anticodons 
B)  ribosomes and tRNA 
C)  several transcription factors 
D)  aminoacyl-tRNA synthetase 
A)  anticodons 
B)  ribosomes and tRNA 
C)  several transcription factors 
D)  aminoacyl-tRNA synthetase

Question 18

The genetic code is essentially the same for all organisms. From this, one can logically assume which of the following statements to be true?

Accepted Answer

A)  A gene from an organism can theoretically be expressed by any other organism. 
B)  DNA was the first genetic material. 
C)  The same codons in different organisms translate into different amino acids. 
D)  Different organisms have different types of amino acids. 
A)  A gene from an organism can theoretically be expressed by any other organism. 
B)  DNA was the first genetic material. 
C)  The same codons in different organisms translate into different amino acids. 
D)  Different organisms have different types of amino acids.

Question 19

An original section of DNA has the base sequence AGCGTTACCGT. A mutation in this DNA strand results in the base sequence AGGCGTTACCGT. What type of mutation does this change represent?

Accepted Answer

A)  a missense mutation 
B)  a point mutation 
C)  a silent mutation 
D)  frameshift mutation 
A)  a missense mutation 
B)  a point mutation 
C)  a silent mutation 
D)  frameshift mutation

Question 20

Which of the following processes is the first event to take place in translation in eukaryotes?

Accepted Answer

A)  base pairing of activated methionine-tRNA to AUG of the messenger RNA 
B)  binding of the larger ribosomal subunit to smaller ribosomal subunits 
C)  the ribosome reaches a stop codon 
D)  the small subunit of the ribosome recognizes and attaches to the 5′ cap of mRNA 
A)  base pairing of activated methionine-tRNA to AUG of the messenger RNA 
B)  binding of the larger ribosomal subunit to smaller ribosomal subunits 
C)  the ribosome reaches a stop codon 
D)  the small subunit of the ribosome recognizes and attaches to the 5′ cap of mRNA

Exam 17: Gene Expression: From Gene to Protein

Which of the following processes occurs when termination of translation takes place?

Use the figure to answer the question. The figure represents tRNA that recognizes and binds a particular amino acid (in this instance, phenylalanine). Which codon on the mRNA strand codes for this amino acid?

A single base substitution mutation is likely to have a less deleterious effect when the base change exhibits which of the following results?

The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single codon. What is the result of this type of mutation?

Use the figure to answer the question. What type of bonding is responsible for maintaining the shape of the tRNA molecule shown in the figure?

Which of the following processes occurs in eukaryotic gene expression?

Which of the following properties is associated with a protein that will be secreted from a eukaryotic cell?

Which of the following statements correctly describes Archibald Garrod's hypothesis for how "inborn errors of metabolism" such as alkaptonuria occur?

Which of the following statements correctly describes a ribozyme?

Post-translational modifications of proteins may include which of the following processes?

Which of the following processes occurs during transcription?

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

Which of the following is not true of RNA processing?

The following question refers to this table of codons. 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?

Transcription in eukaryotes requires which of the following molecules in addition to RNA polymerase?

The genetic code is essentially the same for all organisms. From this, one can logically assume which of the following statements to be true?

An original section of DNA has the base sequence AGCGTTACCGT. A mutation in this DNA strand results in the base sequence AGGCGTTACCGT. What type of mutation does this change represent?

Which of the following processes is the first event to take place in translation in eukaryotes?

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

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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

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DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

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Plant Diversity I: How Plants Colonized Land

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An Overview of Animal Diversity

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Basic Principles of Animal Form and Function

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Hormones and the Endocrine System

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