DNA Replication and Transcription Quizzes: Test Your Knowledge

Question 1

During DNA replication, which enzyme separates the DNA strands?

Accepted Answer

Helicase

Answer

DNA polymerase

Answer

RNA polymerase

Answer

Ligase

Question 2

The primary function of RNA polymerase in transcription is to:

Accepted Answer

Synthesize a complementary mRNA strand using a DNA template

Answer

Proofread and correct errors in the newly synthesized mRNA

Answer

Join individual RNA nucleotides together

Answer

Unwind the DNA double helix

Question 3

Which of the following base pairs is not present in DNA?

Accepted Answer

Adenine-Uracil

Answer

Adenine-Thymine

Answer

Cytosine-Guanine

Answer

Guanine-Cytosine

Question 4

Okazaki fragments are:

Accepted Answer

Short, newly synthesized DNA strands on the lagging strand during replication

Answer

Enzymes that proofread and correct errors in the newly synthesized DNA

Answer

Proteins that bind to DNA to regulate gene expression

Answer

The individual nucleotides that are added to the growing DNA strand

Question 5

Which of the following statements about transcription is accurate?

Accepted Answer

It occurs in the nucleus of eukaryotic cells.

Answer

It is catalyzed by DNA polymerase.

Answer

It produces a complementary mRNA strand using an RNA template.

Answer

It occurs exclusively in prokaryotic cells.

Question 6

Ribosomes play a crucial role in:

Accepted Answer

Translating mRNA into a sequence of amino acids

Answer

Synthesizing mRNA molecules

Answer

Proofreading and correcting errors in newly synthesized proteins

Answer

Packaging proteins into vesicles for transport

Question 7

During DNA replication, which enzyme is responsible for separating the two strands of the double helix?

Accepted Answer

Helicase

Answer

Primase

Answer

Polymerase

Answer

Ligase

Question 8

In DNA, what is the name of the non-coding region that acts as a binding site for RNA polymerase?

Accepted Answer

Promoter

Answer

Exon

Answer

Intron

Answer

Operator

Question 9

Which of the following characteristics is unique to eukaryotic genes?

Accepted Answer

Contains introns

Answer

Is transcribed by RNA polymerase I

Answer

Lacks a promoter region

Answer

Always resides on a single chromosome

Question 10

What is the main purpose of RNA splicing?

Accepted Answer

To remove introns from pre-mRNA

Answer

To add a polyadenylated tail to mRNA

Answer

To modify RNA bases

Answer

To bind to the ribosome

Question 11

Which of the following is not a function of DNA polymerase?

Accepted Answer

Unwinding the DNA double helix

Answer

Proofreading

Answer

Adding nucleotides to the 3' end of a growing DNA strand

Answer

Joining Okazaki fragments

Question 12

What is the role of the termination sequence in transcription?

Accepted Answer

Separates the RNA polymerase from the DNA template

Answer

Adds a polyadenylated tail to the mRNA

Answer

Initiates translation

Answer

Removes introns from the pre-mRNA

Question 13

Which enzyme is responsible for breaking the hydrogen bonds holding the two strands of DNA apart during replication?

Accepted Answer

Helicase

Answer

Polymerase

Answer

Topoisomerase

Answer

Primase

Question 14

Which enzyme synthesizes the RNA primers that provide a starting point for DNA polymerase during replication?

Accepted Answer

Primase

Answer

Polymerase

Answer

Helicase

Answer

Ligase

Question 15

Where does transcription occur in eukaryotic cells?

Accepted Answer

Nucleus

Answer

Cytoplasm

Answer

Ribosomes

Answer

Golgi apparatus

Question 16

Which of the following is NOT a function of introns in eukaryotic genes?

Accepted Answer

They enhance gene expression

Answer

They contain non-coding sequences

Answer

They are removed during RNA splicing

Answer

They regulate protein synthesis

Question 17

Which modification is added to the 5' end of eukaryotic mRNA?

Accepted Answer

5' cap

Answer

3' polyadenylation

Answer

Methylation

Answer

Splicing

Question 18

Which technique separates DNA fragments based on their size and electrical charge?

Accepted Answer

Gel electrophoresis

Answer

DNA sequencing

Answer

PCR

Answer

Southern blotting

Question 19

What is the purpose of the central dogma of molecular biology?

Accepted Answer

To describe the flow of genetic information

Answer

To explain how proteins are synthesized

Answer

To predict the structure of DNA

Answer

To diagnose genetic diseases

Question 20

Which of the following enzymes catalyzes the polymerization of RNA nucleotides during transcription?

Accepted Answer

RNA polymerase

Answer

Reverse transcriptase

Answer

DNA polymerase

Answer

Helicase

Question 21

During DNA replication, which enzyme is responsible for unwinding the DNA double helix, separating the two strands?

Accepted Answer

DNA helicase

Answer

DNA ligase

Answer

DNA polymerase

Answer

Topoisomerase

Question 22

In DNA replication, the lagging strand is synthesized discontinuously, forming short fragments known as:

Accepted Answer

Okazaki fragments

Answer

Introns

Answer

Primers

Answer

Telomeres

Question 23

What is the primary function of RNA polymerase during transcription?

Accepted Answer

Synthesizes RNA using a DNA template.

Answer

Proofreads newly synthesized DNA.

Answer

Joins Okazaki fragments.

Answer

Unwinds the DNA double helix.

Question 24

The process of copying a DNA sequence into an RNA sequence is called:

Accepted Answer

Transcription

Answer

Splicing

Answer

Replication

Answer

Translation

Question 25

What is the significance of the promoter region within a gene?

Accepted Answer

It serves as a binding site for RNA polymerase, initiating transcription.

Answer

It regulates the rate of translation.

Answer

It contains the termination sequence for transcription.

Answer

It codes for the start codon.

Question 26

Which statement accurately describes DNA replication?

Accepted Answer

DNA replication is semi-conservative, meaning each new DNA molecule comprises one original strand and one newly synthesized strand.

Answer

DNA replication is a conservative process, with both new DNA molecules containing entirely newly synthesized strands.

Answer

DNA replication occurs in the cytoplasm of the cell.

Answer

DNA replication is a random process, with no specific mechanism for copying the genetic information.

Question 27

A mutation within the coding sequence of a gene can directly lead to:

Accepted Answer

A change in the amino acid sequence of the protein encoded by the gene.

Answer

A change in the location of the gene on a chromosome.

Answer

A change in the promoter region of the gene.

Answer

An increase in the rate of transcription.

Question 28

What is the primary function of the 5' cap and poly-A tail found on mRNA molecules?

Accepted Answer

They protect the mRNA from degradation and enhance translation efficiency.

Answer

They bind to ribosomes during transcription.

Answer

They code for specific amino acids.

Answer

They regulate the rate of DNA replication.

Question 29

What is a key structural difference between DNA and RNA?

Accepted Answer

DNA contains deoxyribose sugar, while RNA contains ribose sugar.

Answer

DNA is found in the nucleus, while RNA is found only in the cytoplasm.

Answer

DNA is single-stranded, while RNA is double-stranded.

Answer

DNA contains the base uracil, while RNA contains the base thymine.