Original Copy, 100% Verified Questions and Answers
Instructions
This document contains 80 original multiple-choice questions for the CHEM 210 Bio-
chemistry Module 6 Exam (2025/2026), focusing on nucleic acids, gene expression, and
molecular biology techniques. Each question includes four answer choices, a verified cor-
rect answer, and a detailed explanation based on biochemistry principles. Use this guide
to prepare for the exam. The content is formatted for high-quality PDF output.
Questions
Question 1: What is the primary function of DNA in a cell?
a) Catalyzing biochemical reactions
b) Storing genetic information
c) Transporting amino acids
d) Regulating membrane transport
Correct Answer: b) Storing genetic information
Explanation: DNA (deoxyribonucleic acid) serves as the hereditary material in
cells, storing genetic information in the sequence of its nucleotide bases (adenine,
thymine, cytosine, guanine). This information encodes instructions for protein
synthesis and cellular functions. DNA does not catalyze reactions, transport amino
acids, or regulate membrane transport.
Question 2: Which nucleotide base is found in RNA but not in DNA?
a) Adenine
b) Thymine
c) Uracil
d) Guanine
Correct Answer: c) Uracil
Explanation: RNA contains uracil instead of thymine, which is found in DNA.
Uracil pairs with adenine during transcription, while thymine pairs with adenine in
DNA replication. Adenine, guanine, and cytosine are common to both DNA and
RNA.
Question 3: What is the role of the promoter region in transcription?
a) Terminates transcription
b) Initiates translation
c) Binds RNA polymerase
d) Splices introns
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, Correct Answer: c) Binds RNA polymerase
Explanation: The promoter is a DNA sequence that serves as the binding site for
RNA polymerase, initiating transcription by unwinding the DNA and synthesizing
mRNA. It does not terminate transcription, initiate translation, or splice introns.
Question 4: Which enzyme is responsible for synthesizing RNA from a DNA template?
a) DNA polymerase
b) RNA polymerase
c) Reverse transcriptase
d) Ligase
Correct Answer: b) RNA polymerase
Explanation: RNA polymerase synthesizes RNA by adding nucleotides complemen-
tary to the DNA template during transcription. DNA polymerase synthesizes DNA,
reverse transcriptase synthesizes DNA from RNA, and ligase joins DNA fragments.
Question 5: What is the function of the 5’ cap on eukaryotic mRNA?
a) Initiates replication
b) Enhances mRNA stability and translation
c) Terminates transcription
d) Splices exons
Correct Answer: b) Enhances mRNA stability and translation
Explanation: The 5’ cap, a modified guanine nucleotide, protects eukaryotic mRNA
from degradation and facilitates ribosome binding for translation. It does not ini-
tiate replication, terminate transcription, or splice exons.
Question 6: What is the role of the poly-A tail in eukaryotic mRNA?
a) Initiates DNA replication
b) Protects mRNA from degradation
c) Binds tRNA during translation
d) Catalyzes peptide bond formation
Correct Answer: b) Protects mRNA from degradation
Explanation: The poly-A tail, a string of adenine nucleotides added to the 3’ end
of eukaryotic mRNA, enhances mRNA stability by protecting it from exonucleases
and aids in nuclear export and translation.
Question 7: Which of the following is a key component of a ribosome?
a) DNA
b) rRNA
c) mRNA
d) tRNA
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, Correct Answer: b) rRNA
Explanation: Ribosomes are composed of ribosomal RNA (rRNA) and proteins,
forming the machinery for protein synthesis. mRNA provides the template, and
tRNA delivers amino acids, but neither is a structural component of the ribosome.
Question 8: What is the start codon for translation in eukaryotes?
a) UAA
b) AUG
c) UAG
d) UGA
Correct Answer: b) AUG
Explanation: The AUG codon codes for methionine and serves as the start codon
for translation in eukaryotes, signaling the ribosome to begin protein synthesis.
UAA, UAG, and UGA are stop codons.
Question 9: Which molecule delivers amino acids to the ribosome during translation?
a) mRNA
b) tRNA
c) rRNA
d) snRNA
Correct Answer: b) tRNA
Explanation: Transfer RNA (tRNA) carries specific amino acids to the ribosome,
matching its anticodon to the mRNA codon during translation. mRNA provides
the template, rRNA forms the ribosome, and snRNA is involved in splicing.
Question 10: What is the function of the TATA box in eukaryotic transcription?
a) Terminates transcription
b) Binds transcription factors
c) Splices introns
d) Initiates translation
Correct Answer: b) Binds transcription factors
Explanation: The TATA box, located in the promoter region of eukaryotic genes,
binds transcription factors (e.g., TBP in the TFIID complex), facilitating RNA
polymerase II recruitment for transcription initiation.
Question 11: What is the role of introns in eukaryotic genes?
a) Code for amino acids
b) Regulate translation
c) Non-coding sequences removed during splicing
d) Bind RNA polymerase
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