Gene Expression: A Comprehensive Guide for Biology MSc Students

Question 1

Which of the following is NOT a component of the transcription initiation complex in eukaryotes?

Accepted Answer

Histone deacetylase (HDAC)

Answer

RNA polymerase II

Answer

TATA-binding protein (TBP)

Question 2

Which step is not directly involved in the process of transcription?

Accepted Answer

Splicing of the RNA molecule

Answer

RNA polymerase binding to the promoter

Answer

Polymerization of RNA nucleotides

Question 3

Where on the ribosome does translation initiation take place?

Accepted Answer

A site

Answer

P site

Answer

E site

Answer

tRNA docking site

Question 4

In protein synthesis, what is the primary function of tRNA?

Accepted Answer

Transporting amino acids

Answer

Catalyzing peptide bond formation

Answer

Decoding the mRNA sequence

Answer

Stabilizing the ribosome

Question 5

What is the significance of bacteria's Shine-Dalgarno sequence?

Accepted Answer

It is the ribosome's binding site during translation initiation.

Answer

It is the promoter region of bacterial genes.

Answer

It aids in proper mRNA cleavage during termination.

Answer

It aids in charging tRNA molecules with amino acids.

Question 6

Define a codon.

Accepted Answer

A three-nucleotide RNA sequence encoding a specific amino acid.

Answer

A three-nucleotide DNA sequence encoding a specific protein.

Answer

A three-amino-acid sequence encoding a specific RNA molecule.

Answer

A three-protein sequence encoding a specific DNA molecule.

Question 7

Which of the following is NOT a fundamental step in the process of transcription?

Accepted Answer

RNA splicing

Answer

Initiation

Answer

Elongation

Answer

Termination

Question 8

Pre-mRNA undergoes modifications before becoming mature mRNA. What is the term for the process that removes non-coding regions (introns)?

Accepted Answer

Splicing

Answer

Capping

Answer

Polyadenylation

Answer

Translation

Question 9

Where does protein synthesis occur within a cell?

Accepted Answer

Ribosomes

Answer

Nucleus

Answer

Mitochondria

Answer

Endoplasmic reticulum

Question 10

Which of the following processes is unique to eukaryotic gene expression?

Accepted Answer

Splicing

Answer

Translation

Answer

Transcription

Answer

Initiation

Question 11

What is the fundamental purpose of the genetic code?

Accepted Answer

Determining the sequence of amino acids in proteins

Answer

Regulating gene expression

Answer

Storing genetic information

Answer

Translating RNA into protein

Question 12

What is the primary purpose of gene regulation?

Accepted Answer

Controlling when and where genes are expressed

Answer

Modifying the structure of proteins

Answer

Repairing damaged DNA

Answer

Translating mRNA into protein

Question 13

What is the most accurate description of transcription?

Accepted Answer

Creating an RNA molecule that matches a DNA template.

Answer

Changing RNA into a protein.

Answer

Adjusting RNA after transcription to make it work.

Answer

Controlling RNA production to regulate gene expression.

Question 14

What is the primary function of the ribosome in translation?

Accepted Answer

Facilitating the assembly of amino acids and tRNA

Answer

Unraveling the DNA double helix

Answer

Synthesizing mRNA

Answer

Modifying proteins post-translationally

Question 15

What is the function of the promoter region in gene expression?

Accepted Answer

Binding RNA polymerase and initiating transcription

Answer

Terminating transcription

Answer

Excising introns from mRNA

Answer

Translating mRNA into protein

Question 16

Which codon codes for the amino acid methionine?

Accepted Answer

AUG

Answer

UUA

Answer

GCA

Answer

AUU

Question 17

How can a single gene produce multiple proteins?

Accepted Answer

Alternative splicing

Answer

Gene duplication

Answer

Point mutations

Answer

Transposable elements

Question 18

Which of the following is NOT a factor that can affect gene expression?

Accepted Answer

Molecular weight

Answer

Environmental cues

Answer

Hormonal signals

Answer

Genetic mutations

Question 19

What do introns primarily contain in eukaryotic genes?

Accepted Answer

Regions removed during splicing

Answer

Protein-coding sequences

Answer

Gene expression regulators

Answer

DNA replication initiators

Question 20

How does RNA polymerase identify the starting point for transcription on the DNA template?

Accepted Answer

Recognition of specific DNA sequences called promoters

Answer

Scanning the DNA for the longest continuous open reading frame

Answer

Binding to the 5' cap of a mature RNA molecule

Question 21

Which enzyme is responsible for catalyzing the formation of mRNA during transcription?

Accepted Answer

RNA polymerase

Answer

DNA polymerase

Answer

Reverse transcriptase

Answer

Helicase

Question 22

What process translates the genetic code in mRNA into a sequence of amino acids?

Accepted Answer

Translation

Answer

Replication

Answer

Transcription

Answer

Mutation

Question 23

Which molecule aids in transferring amino acids to the ribosome during translation?

Accepted Answer

tRNA

Answer

mRNA

Answer

rRNA

Answer

DNA

Question 24

Describe the sequential steps of transcription.

Accepted Answer

Initiation, elongation, termination

Answer

Elongation, initiation, termination

Answer

Termination, initiation, elongation

Answer

Initiation, termination, elongation

Question 25

Which of the following is not involved in transcriptional regulation?

Accepted Answer

tRNA

Answer

Transcription factors

Answer

Enhancers

Answer

Silencers

Question 26

What role does the anticodon of a tRNA molecule play?

Accepted Answer

Binds to a specific codon on mRNA

Answer

Binds to the promoter region of a gene

Answer

Binds to the ribosome

Answer

Catalyzes the formation of peptide bonds

Question 27

Distinguish between constitutive and inducible gene expression.

Accepted Answer

Constitutive genes exhibit constant expression, while inducible genes only express in response to specific stimuli

Answer

Inducible genes exhibit constant expression, while constitutive genes only express in response to specific stimuli

Answer

Constitutive genes only express in certain cell types, while inducible genes express in all cell types

Answer

Inducible genes only express in certain cell types, while constitutive genes express in all cell types

Question 28

The process of creating mRNA from a DNA template is known as:

Accepted Answer

Transcription

Answer

Translation

Answer

Replication

Answer

Mutation

Question 29

The anticodon of a tRNA molecule:

Accepted Answer

Complements the codon in the mRNA

Answer

Determines the amino acid to be added to the growing polypeptide

Answer

Is responsible for binding to the ribosome

Answer

Contains a sequence complementary to the promoter region

Question 30

Which of the following is a post-translational modification?

Accepted Answer

Phosphorylation

Answer

Splicing

Answer

Capping

Answer

Polyadenylation

Question 31

The operon model of gene regulation is primarily associated with:

Accepted Answer

Bacteria

Answer

Eukaryotes

Answer

Archaea

Answer

Viruses

Question 32

Which enzyme is responsible for synthesizing RNA during transcription?

Accepted Answer

RNA polymerase

Answer

DNA polymerase

Answer

Reverse transcriptase

Answer

Primase

Question 33

What is the messenger molecule that carries genetic information from DNA to the ribosome called?

Accepted Answer

mRNA

Answer

tRNA

Answer

rRNA

Answer

snRNA

Question 34

The correct sequence of events during transcription is:

Accepted Answer

Promoter binding, initiation, elongation, termination

Answer

Initiation, elongation, termination, promoter binding

Answer

Elongation, initiation, termination, promoter binding

Answer

Termination, elongation, initiation, promoter binding

Question 35

Which of the following is NOT a type of post-transcriptional modification?

Accepted Answer

Translation

Answer

Splicing

Answer

Polyadenylation

Answer

Methylation

Question 36

Which region of DNA controls the expression of a gene?

Accepted Answer

Promoter

Answer

Enhancer

Answer

Terminator

Answer

Operator

Question 37

What is the key difference between constitutive and inducible genes?

Accepted Answer

Constitutive genes are expressed all the time, while inducible genes are only expressed under specific conditions

Answer

Inducible genes are expressed all the time, while constitutive genes are only expressed under specific conditions

Answer

Constitutive genes are regulated by promoters, while inducible genes are regulated by enhancers

Answer

Inducible genes are regulated by promoters, while constitutive genes are regulated by enhancers

Question 38

Which enzyme is primarily responsible for initiating transcription in eukaryotic cells?

Accepted Answer

RNA polymerase II

Answer

DNA polymerase

Answer

RNA polymerase I

Answer

Helicase

Question 39

What is the main function of ribosomes in protein synthesis?

Accepted Answer

To assemble amino acids into a polypeptide chain

Answer

To transport mRNA from the nucleus to the cytoplasm

Answer

To replicate DNA

Answer

To synthesize tRNA

Question 40

State the central dogma of molecular biology.

Accepted Answer

DNA -> RNA -> Protein

Answer

RNA -> DNA -> Protein

Answer

Protein -> DNA -> RNA

Answer

RNA -> Protein -> DNA

Question 41

What is the primary function of promoters in gene expression?

Accepted Answer

To bind RNA polymerase and initiate transcription

Answer

To terminate transcription

Answer

To splice mRNA

Answer

To translate mRNA

Question 42

What is the main purpose of alternative splicing?

Accepted Answer

To produce different protein isoforms from a single gene

Answer

To repair damaged RNA molecules

Answer

To regulate gene expression

Answer

To enhance mRNA stability

Question 43

Which technique is commonly used to quantify gene expression levels?

Accepted Answer

Quantitative real-time PCR

Answer

Southern blotting

Answer

Flow cytometry

Answer

Immunohistochemistry

Question 44

What is the primary role of epigenetics in gene expression?

Accepted Answer

To modify gene expression patterns without altering the DNA sequence

Answer

To repair damaged DNA

Answer

To regulate cell cycle progression

Answer

To promote DNA methylation