BIOS 210 GENETICS: COMPREHENSIVE 200-QUESTION EXAM
BANK COMPLETE WITH VERIFIED ANSWERS
Table of Contents
Section Domain Approx. Page
Questions Reference
1 DNA & RNA Structure 20 1
2 DNA Replication, Recombination & 20 3
Repair
3 Transcription & RNA Processing 20 5
4 Translation & the Genetic Code 20 7
5 Gene Regulation in Prokaryotes & 20 9
Eukaryotes
6 Mendelian Genetics & Extensions 20 11
7 Chromosomal Basis of Inheritance 20 13
8 Mutations & Genetic Disorders 20 15
9 Population Genetics & Evolution 20 17
10 Biotechnology, Genomics & Ethics 20 19
Section 1: DNA & RNA Structure (Questions 1-20)
Subsection 1.1: Nucleotides and Chemical Bonds (1-7)
1. What are the three components of a DNA nucleotide?
A) Sugar, sulfate, and base
B) Amino acid, phosphate, and sugar
,C) Lipid, base, and phosphate
D) Sugar, phosphate, and nitrogenous base
Answer: D
Rationale: A DNA nucleotide is composed of a deoxyribose sugar, a
phosphate group, and a nitrogenous base.
2. Which type of bond connects the phosphate group of one
nucleotide to the sugar of the next nucleotide in a DNA strand?
A) Phosphodiester bond
B) Hydrogen bond
C) Glycosidic bond
D) Peptide bond
Answer: A
Rationale: Phosphodiester bonds form the sugar-phosphate backbone
of nucleic acids.
3. What is the difference between a nucleoside and a nucleotide?
A) A nucleoside has a phosphate group, while a nucleotide does not.
B) A nucleoside contains a base, while a nucleotide does not.
C) A nucleoside has a sulfate group, while a nucleotide does not.
D) A nucleoside lacks a phosphate group, while a nucleotide contains
one.
Answer: D
Rationale: A nucleoside consists of a sugar and a base, whereas a
nucleotide includes a phosphate group.
4. Which carbon of the deoxyribose sugar is attached to the
nitrogenous base?
A) 5' carbon
B) 3' carbon
,C) 1' carbon
D) 2' carbon
Answer: C
Rationale: The nitrogenous base is attached to the 1' carbon of the
pentose sugar via a glycosidic bond.
5. What distinguishes deoxyribose from ribose?
A) Deoxyribose has an extra hydroxyl group at the 2' carbon.
B) Deoxyribose lacks a hydroxyl group at the 2' carbon.
C) Deoxyribose has a phosphate group at the 2' carbon.
D) Deoxyribose lacks a hydroxyl group at the 3' carbon.
Answer: B
Rationale: Ribose has a hydroxyl group at the 2' position, while
deoxyribose has a hydrogen atom at this position.
6. Which of the following is a purine base?
A) Thymine
B) Cytosine
C) Adenine
D) Uracil
Answer: C
Rationale: Adenine and Guanine are purines, characterized by a double-
ring structure.
7. Which of the following is a pyrimidine base?
A) Cytosine
B) Adenine
C) Guanine
D) Purine
Answer: A
, Rationale: Cytosine, Thymine, and Uracil are pyrimidines, characterized
by a single-ring structure.
Subsection 1.2: DNA Double Helix and Properties (8-14)
8. According to Chargaff's rules, in a double-stranded DNA molecule,
the amount of adenine is equal to the amount of:
A) Guanine
B) Cytosine
C) Thymine
D) Uracil
Answer: C
Rationale: Adenine pairs specifically with Thymine via two hydrogen
bonds.
9. How many hydrogen bonds form between guanine and cytosine in
DNA?
A) One
B) Two
C) Three
D) Four
Answer: C
Rationale: Guanine and Cytosine form three hydrogen bonds, making
the interaction stronger than A-T pairing.
10. What is the overall structure of the DNA double helix as proposed
by Watson and Crick?
A) A left-handed helix with parallel strands.
B) A right-handed helix with parallel strands.
C) A right-handed helix with antiparallel strands.
D) A left-handed helix with antiparallel strands.
BANK COMPLETE WITH VERIFIED ANSWERS
Table of Contents
Section Domain Approx. Page
Questions Reference
1 DNA & RNA Structure 20 1
2 DNA Replication, Recombination & 20 3
Repair
3 Transcription & RNA Processing 20 5
4 Translation & the Genetic Code 20 7
5 Gene Regulation in Prokaryotes & 20 9
Eukaryotes
6 Mendelian Genetics & Extensions 20 11
7 Chromosomal Basis of Inheritance 20 13
8 Mutations & Genetic Disorders 20 15
9 Population Genetics & Evolution 20 17
10 Biotechnology, Genomics & Ethics 20 19
Section 1: DNA & RNA Structure (Questions 1-20)
Subsection 1.1: Nucleotides and Chemical Bonds (1-7)
1. What are the three components of a DNA nucleotide?
A) Sugar, sulfate, and base
B) Amino acid, phosphate, and sugar
,C) Lipid, base, and phosphate
D) Sugar, phosphate, and nitrogenous base
Answer: D
Rationale: A DNA nucleotide is composed of a deoxyribose sugar, a
phosphate group, and a nitrogenous base.
2. Which type of bond connects the phosphate group of one
nucleotide to the sugar of the next nucleotide in a DNA strand?
A) Phosphodiester bond
B) Hydrogen bond
C) Glycosidic bond
D) Peptide bond
Answer: A
Rationale: Phosphodiester bonds form the sugar-phosphate backbone
of nucleic acids.
3. What is the difference between a nucleoside and a nucleotide?
A) A nucleoside has a phosphate group, while a nucleotide does not.
B) A nucleoside contains a base, while a nucleotide does not.
C) A nucleoside has a sulfate group, while a nucleotide does not.
D) A nucleoside lacks a phosphate group, while a nucleotide contains
one.
Answer: D
Rationale: A nucleoside consists of a sugar and a base, whereas a
nucleotide includes a phosphate group.
4. Which carbon of the deoxyribose sugar is attached to the
nitrogenous base?
A) 5' carbon
B) 3' carbon
,C) 1' carbon
D) 2' carbon
Answer: C
Rationale: The nitrogenous base is attached to the 1' carbon of the
pentose sugar via a glycosidic bond.
5. What distinguishes deoxyribose from ribose?
A) Deoxyribose has an extra hydroxyl group at the 2' carbon.
B) Deoxyribose lacks a hydroxyl group at the 2' carbon.
C) Deoxyribose has a phosphate group at the 2' carbon.
D) Deoxyribose lacks a hydroxyl group at the 3' carbon.
Answer: B
Rationale: Ribose has a hydroxyl group at the 2' position, while
deoxyribose has a hydrogen atom at this position.
6. Which of the following is a purine base?
A) Thymine
B) Cytosine
C) Adenine
D) Uracil
Answer: C
Rationale: Adenine and Guanine are purines, characterized by a double-
ring structure.
7. Which of the following is a pyrimidine base?
A) Cytosine
B) Adenine
C) Guanine
D) Purine
Answer: A
, Rationale: Cytosine, Thymine, and Uracil are pyrimidines, characterized
by a single-ring structure.
Subsection 1.2: DNA Double Helix and Properties (8-14)
8. According to Chargaff's rules, in a double-stranded DNA molecule,
the amount of adenine is equal to the amount of:
A) Guanine
B) Cytosine
C) Thymine
D) Uracil
Answer: C
Rationale: Adenine pairs specifically with Thymine via two hydrogen
bonds.
9. How many hydrogen bonds form between guanine and cytosine in
DNA?
A) One
B) Two
C) Three
D) Four
Answer: C
Rationale: Guanine and Cytosine form three hydrogen bonds, making
the interaction stronger than A-T pairing.
10. What is the overall structure of the DNA double helix as proposed
by Watson and Crick?
A) A left-handed helix with parallel strands.
B) A right-handed helix with parallel strands.
C) A right-handed helix with antiparallel strands.
D) A left-handed helix with antiparallel strands.
