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BIOD 210 GENETICS MODULE 4 2026 EXAM:
MUTATIONS AND DNA REPAIR COMPLETE
(160) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED
RATIONALES|GRADED A+.
BIOD
Prepare for the BIOD 210 Genetics Module 4 Exam with practice questions
covering mutation types, causes, effects, DNA repair mechanisms, and
related topics. This study guide helps reinforce essential genetics
knowledge and supports effective biology exam preparation. Designed to
improve problem-solving skills and boost confidence in understanding
hereditary and genetic processes. Suitable for biology, pre-med, nursing,
and allied health students.
MULTIPLE CHOICE.
Section 1: Mutation Definitions and Classifications (Questions
1–30)
1. What is the broadest definition of a mutation?
A) A change in the amino acid sequence of a protein
B) A heritable change in the nucleotide sequence of DNA
C) A change in the phenotype of an organism
D) An alteration in chromosome number
Answer: B. A heritable change in the nucleotide sequence of DNA
Explanation: A mutation is any heritable change in the DNA
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sequence. It can be small (point mutations) or large (chromosomal
rearrangements), and may or may not affect phenotype.
2. A mutation that occurs in a gamete is classified as:
A) Somatic mutation
B) Germline mutation
C) Induced mutation
D) Spontaneous mutation
Answer: B. Germline mutation
Explanation: Germline mutations occur in cells that produce
gametes (eggs or sperm) and can be passed to offspring. Somatic
mutations occur in body cells and are not inherited.
3. Which of the following is an example of a spontaneous
mutation?
A) Mutation caused by UV radiation
B) Mutation caused by a chemical mutagen
C) Mutation due to replication error
D) Mutation induced by X-rays
Answer: C. Mutation due to replication error
Explanation: Spontaneous mutations arise naturally from DNA
replication errors, depurination, deamination, or oxidative damage,
without external mutagens.
4. A point mutation that changes a single nucleotide but does
not change the amino acid is called:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
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Answer: C. Silent mutation
Explanation: Silent mutations do not alter the amino acid due to the
degeneracy of the genetic code.
5. A mutation that changes a codon from UAC (tyrosine) to UAG
(stop codon) is an example of:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
Answer: B. Nonsense mutation
Explanation: A nonsense mutation creates a premature stop
codon, leading to truncated protein.
6. A mutation that substitutes a purine for a pyrimidine (e.g., A to
C) is called a:
A) Transition
B) Transversion
C) Inversion
D) Deletion
Answer: B. Transversion
Explanation: A transversion changes a purine to a pyrimidine or vice
versa. A transition changes a purine to another purine (A↔G) or
pyrimidine to another pyrimidine (C↔T).
7. Which type of mutation results from the insertion or deletion
of nucleotides in a coding region, altering the reading frame?
A) Point mutation
B) Frameshift mutation
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C) Nonsense mutation
D) Missense mutation
Answer: B. Frameshift mutation
Explanation: Insertions or deletions (indels) not in multiples of 3
shift the reading frame, altering all downstream amino acids.
8. The β-globin mutation responsible for sickle cell anemia is a:
A) Frameshift mutation
B) Nonsense mutation
C) Missense mutation (Glu6Val)
D) Silent mutation
Answer: C. Missense mutation (Glu6Val)
Explanation: A single nucleotide change (A→T) substitutes valine for
glutamic acid at position 6 of the β-globin chain.
9. True or False: All mutations are harmful.
A) True
B) False
Answer: B. False
Explanation: Mutations can be harmful, neutral, or beneficial
depending on environment and genetic context. Some mutations
provide adaptive advantages.
10. A mutation that occurs in a non-coding region such as an
intron may have no effect if it does not affect splicing. This is
often called:
A) Silent mutation
B) Neutral mutation
BIOD 210 GENETICS MODULE 4 2026 EXAM:
MUTATIONS AND DNA REPAIR COMPLETE
(160) CURRENT TESTING QUESTIONS AND
CORRECT ANSWERS WITH DETAILED
RATIONALES|GRADED A+.
BIOD
Prepare for the BIOD 210 Genetics Module 4 Exam with practice questions
covering mutation types, causes, effects, DNA repair mechanisms, and
related topics. This study guide helps reinforce essential genetics
knowledge and supports effective biology exam preparation. Designed to
improve problem-solving skills and boost confidence in understanding
hereditary and genetic processes. Suitable for biology, pre-med, nursing,
and allied health students.
MULTIPLE CHOICE.
Section 1: Mutation Definitions and Classifications (Questions
1–30)
1. What is the broadest definition of a mutation?
A) A change in the amino acid sequence of a protein
B) A heritable change in the nucleotide sequence of DNA
C) A change in the phenotype of an organism
D) An alteration in chromosome number
Answer: B. A heritable change in the nucleotide sequence of DNA
Explanation: A mutation is any heritable change in the DNA
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sequence. It can be small (point mutations) or large (chromosomal
rearrangements), and may or may not affect phenotype.
2. A mutation that occurs in a gamete is classified as:
A) Somatic mutation
B) Germline mutation
C) Induced mutation
D) Spontaneous mutation
Answer: B. Germline mutation
Explanation: Germline mutations occur in cells that produce
gametes (eggs or sperm) and can be passed to offspring. Somatic
mutations occur in body cells and are not inherited.
3. Which of the following is an example of a spontaneous
mutation?
A) Mutation caused by UV radiation
B) Mutation caused by a chemical mutagen
C) Mutation due to replication error
D) Mutation induced by X-rays
Answer: C. Mutation due to replication error
Explanation: Spontaneous mutations arise naturally from DNA
replication errors, depurination, deamination, or oxidative damage,
without external mutagens.
4. A point mutation that changes a single nucleotide but does
not change the amino acid is called:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
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Answer: C. Silent mutation
Explanation: Silent mutations do not alter the amino acid due to the
degeneracy of the genetic code.
5. A mutation that changes a codon from UAC (tyrosine) to UAG
(stop codon) is an example of:
A) Missense mutation
B) Nonsense mutation
C) Silent mutation
D) Frameshift mutation
Answer: B. Nonsense mutation
Explanation: A nonsense mutation creates a premature stop
codon, leading to truncated protein.
6. A mutation that substitutes a purine for a pyrimidine (e.g., A to
C) is called a:
A) Transition
B) Transversion
C) Inversion
D) Deletion
Answer: B. Transversion
Explanation: A transversion changes a purine to a pyrimidine or vice
versa. A transition changes a purine to another purine (A↔G) or
pyrimidine to another pyrimidine (C↔T).
7. Which type of mutation results from the insertion or deletion
of nucleotides in a coding region, altering the reading frame?
A) Point mutation
B) Frameshift mutation
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C) Nonsense mutation
D) Missense mutation
Answer: B. Frameshift mutation
Explanation: Insertions or deletions (indels) not in multiples of 3
shift the reading frame, altering all downstream amino acids.
8. The β-globin mutation responsible for sickle cell anemia is a:
A) Frameshift mutation
B) Nonsense mutation
C) Missense mutation (Glu6Val)
D) Silent mutation
Answer: C. Missense mutation (Glu6Val)
Explanation: A single nucleotide change (A→T) substitutes valine for
glutamic acid at position 6 of the β-globin chain.
9. True or False: All mutations are harmful.
A) True
B) False
Answer: B. False
Explanation: Mutations can be harmful, neutral, or beneficial
depending on environment and genetic context. Some mutations
provide adaptive advantages.
10. A mutation that occurs in a non-coding region such as an
intron may have no effect if it does not affect splicing. This is
often called:
A) Silent mutation
B) Neutral mutation
