BIO 340 Holechek Exam Two | Exam Questions and
Answers with Verified Solutions | Latest 2026
Update
,Gene Expression, Protein Products, Phenotype & Mutations
1. What is the primary relationship between a gene and its protein product?
A. A gene always produces multiple unrelated proteins
B. A gene contains information that can direct production of a functional RNA or protein
C. A protein determines the DNA sequence of every gene
D. Genes are produced from proteins
Answer: B. A gene contains information that can direct production of a functional RNA or
protein
Rationale: Genes contain hereditary information that can be expressed as functional RNA or, in
many cases, proteins.
2. What ultimately contributes most directly to determining an organism's phenotype?
A. The nucleotide sequence alone
B. The activities of gene products interacting with the environment
C. The number of chromosomes alone
D. DNA replication alone
Answer: B. The activities of gene products interacting with the environment
Rationale: Phenotypes result from the effects of gene products, their interactions, and
environmental influences.
3. The observable characteristics of an organism are collectively called its:
A. Genotype
B. Genome
C. Phenotype
D. Allele
Answer: C. Phenotype
Rationale: Phenotype refers to the observable or measurable characteristics of an organism.
4. A mutation that reduces or eliminates the normal activity of a gene product is generally
called:
,A. Gain-of-function mutation
B. Loss-of-function mutation
C. Silent mutation
D. Regulatory duplication
Answer: B. Loss-of-function mutation
Rationale: Loss-of-function mutations decrease or eliminate the normal function of a gene
product.
5. Which mutation is most likely to completely disrupt a protein's amino acid sequence
downstream of the mutation?
A. Silent substitution
B. Frameshift mutation
C. Conservative substitution
D. Synonymous substitution
Answer: B. Frameshift mutation
Rationale: Insertions or deletions that are not multiples of three shift the reading frame and can
alter many downstream codons.
6. A mutation that changes a codon but still produces the same amino acid is called:
A. Missense
B. Nonsense
C. Silent
D. Frameshift
Answer: C. Silent
Rationale: A silent mutation changes a nucleotide sequence without changing the encoded
amino acid.
7. A mutation changes a codon for an amino acid into a stop codon. This is a:
A. Silent mutation
B. Missense mutation
, C. Nonsense mutation
D. Suppressor mutation
Answer: C. Nonsense mutation
Rationale: A nonsense mutation introduces a premature stop codon, often resulting in a
shortened protein.
8. A mutation that changes one amino acid in a protein to another amino acid is a:
A. Missense mutation
B. Nonsense mutation
C. Silent mutation
D. Frameshift mutation
Answer: A. Missense mutation
Rationale: Missense mutations alter a codon so that a different amino acid is incorporated into
the protein.
9. Which process converts DNA information into an RNA molecule?
A. Translation
B. Replication
C. Transcription
D. Recombination
Answer: C. Transcription
Rationale: Transcription uses a DNA template to synthesize RNA.
10. Which process uses an mRNA sequence to produce a polypeptide?
A. Replication
B. Transcription
C. Translation
D. Transduction
Answer: C. Translation
Answers with Verified Solutions | Latest 2026
Update
,Gene Expression, Protein Products, Phenotype & Mutations
1. What is the primary relationship between a gene and its protein product?
A. A gene always produces multiple unrelated proteins
B. A gene contains information that can direct production of a functional RNA or protein
C. A protein determines the DNA sequence of every gene
D. Genes are produced from proteins
Answer: B. A gene contains information that can direct production of a functional RNA or
protein
Rationale: Genes contain hereditary information that can be expressed as functional RNA or, in
many cases, proteins.
2. What ultimately contributes most directly to determining an organism's phenotype?
A. The nucleotide sequence alone
B. The activities of gene products interacting with the environment
C. The number of chromosomes alone
D. DNA replication alone
Answer: B. The activities of gene products interacting with the environment
Rationale: Phenotypes result from the effects of gene products, their interactions, and
environmental influences.
3. The observable characteristics of an organism are collectively called its:
A. Genotype
B. Genome
C. Phenotype
D. Allele
Answer: C. Phenotype
Rationale: Phenotype refers to the observable or measurable characteristics of an organism.
4. A mutation that reduces or eliminates the normal activity of a gene product is generally
called:
,A. Gain-of-function mutation
B. Loss-of-function mutation
C. Silent mutation
D. Regulatory duplication
Answer: B. Loss-of-function mutation
Rationale: Loss-of-function mutations decrease or eliminate the normal function of a gene
product.
5. Which mutation is most likely to completely disrupt a protein's amino acid sequence
downstream of the mutation?
A. Silent substitution
B. Frameshift mutation
C. Conservative substitution
D. Synonymous substitution
Answer: B. Frameshift mutation
Rationale: Insertions or deletions that are not multiples of three shift the reading frame and can
alter many downstream codons.
6. A mutation that changes a codon but still produces the same amino acid is called:
A. Missense
B. Nonsense
C. Silent
D. Frameshift
Answer: C. Silent
Rationale: A silent mutation changes a nucleotide sequence without changing the encoded
amino acid.
7. A mutation changes a codon for an amino acid into a stop codon. This is a:
A. Silent mutation
B. Missense mutation
, C. Nonsense mutation
D. Suppressor mutation
Answer: C. Nonsense mutation
Rationale: A nonsense mutation introduces a premature stop codon, often resulting in a
shortened protein.
8. A mutation that changes one amino acid in a protein to another amino acid is a:
A. Missense mutation
B. Nonsense mutation
C. Silent mutation
D. Frameshift mutation
Answer: A. Missense mutation
Rationale: Missense mutations alter a codon so that a different amino acid is incorporated into
the protein.
9. Which process converts DNA information into an RNA molecule?
A. Translation
B. Replication
C. Transcription
D. Recombination
Answer: C. Transcription
Rationale: Transcription uses a DNA template to synthesize RNA.
10. Which process uses an mRNA sequence to produce a polypeptide?
A. Replication
B. Transcription
C. Translation
D. Transduction
Answer: C. Translation
