Gene Expression: A Comprehensive Guide for Biotechnology Students

Question 1

Which of the following processes is NOT directly involved in gene expression?

Accepted Answer

Replication

Answer

Transcription

Answer

Translation

Question 2

Identify the correct sequence of gene expression events.

Accepted Answer

Transcription, translation, post-translational modification

Answer

Translation, transcription, post-translational modification

Answer

Post-translational modification, transcription, translation

Answer

Transcription, post-translational modification, translation

Question 3

Describe the primary function of RNA polymerase in transcription.

Accepted Answer

Uncoiling the DNA double helix and synthesizing complementary RNA

Answer

Catalyzing the formation of peptide bonds

Answer

Modifying newly synthesized proteins

Answer

Transporting mRNA from the nucleus to the cytoplasm

Question 4

Define the genetic code.

Accepted Answer

A set of rules that translates DNA nucleotide sequences into protein amino acid sequences

Answer

The sequence of genes on a chromosome

Answer

The process of DNA copying into RNA

Answer

The modification of proteins after translation

Question 5

Provide a definition for an operon.

Accepted Answer

A group of genes transcribed together under a single promoter's control

Answer

A non-coding RNA molecule involved in gene expression regulation

Answer

A protein that catalyzes RNA synthesis

Answer

A region of DNA containing regulatory elements

Question 6

Name the process involved in copying DNA into messenger RNA (mRNA).

Accepted Answer

Transcription

Answer

Translation

Answer

Replication

Answer

Post-transcriptional modification

Question 7

Which type of RNA carries the genetic code from the nucleus to the ribosomes?

Accepted Answer

Messenger RNA (mRNA)

Answer

Ribosomal RNA (rRNA)

Answer

Transfer RNA (tRNA)

Answer

Small nuclear RNA (snRNA)

Question 8

Identify the codon that represents the amino acid methionine.

Accepted Answer

AUG

Answer

UUU

Answer

CCC

Answer

GGG

Question 9

Select the distinction between constitutive and inducible genes.

Accepted Answer

Constitutive genes are perpetually expressed, while inducible genes require specific conditions to be activated.

Answer

Constitutive genes are activated by specific signals, while inducible genes are perpetually expressed.

Answer

Both constitutive and inducible genes require specific signals to be activated.

Answer

There is no distinction between constitutive and inducible genes.

Question 10

Which enzyme plays the crucial role in linking amino acids during translation?

Accepted Answer

Peptidyl transferase

Answer

DNA polymerase

Answer

RNA polymerase

Answer

Ribosome

Question 11

What two components make up the backbone of ribosomes?

Accepted Answer

rRNA and proteins

Answer

mRNA and tRNA

Answer

DNA and RNA polymerase

Answer

Codons and anticodons

Question 12

Which of the following is an exception to the steps involved in transcription?

Accepted Answer

Splicing

Answer

Initiation

Answer

Elongation

Answer

Termination

Question 13

Describe the primary function of ribosomes in the context of translation.

Accepted Answer

Assembling amino acids to form a polypeptide chain

Answer

Providing energy for the translation process

Answer

Decoding the genetic code present in mRNA

Answer

Transcribing DNA into RNA

Question 14

Which of the following is a crucial regulatory element in gene expression?

Accepted Answer

Promoter

Answer

Ribosome

Answer

mRNA

Answer

tRNA

Question 15

Explain the purpose of alternative splicing in gene expression.

Accepted Answer

To generate different protein isoforms from a single gene

Answer

To enhance the efficiency of transcription

Answer

To remove introns from pre-mRNA

Answer

To stabilize mRNA

Question 16

Distinguish between a constitutive promoter and an inducible promoter.

Accepted Answer

Constitutive promoters are constantly activated, while inducible promoters require specific signals to become active.

Answer

Inducible promoters are constantly activated, while constitutive promoters require specific signals to become active.

Answer

Constitutive promoters are solely found in prokaryotes, whereas inducible promoters are exclusively found in eukaryotes.

Answer

Inducible promoters are solely found in prokaryotes, whereas constitutive promoters are exclusively found in eukaryotes.

Question 17

Describe the significance of post-translational modifications in gene expression.

Accepted Answer

They can influence the function, stability, and localization of proteins

Answer

They are essential for protein synthesis to occur

Answer

They occur exclusively in eukaryotic cells

Answer

They have no effect on protein function

Question 18

Which of the following is an example of a genetic disorder resulting from a defect in gene expression?

Accepted Answer

Cystic fibrosis

Answer

Turner syndrome (caused by a missing or incomplete X chromosome)

Answer

Down syndrome (caused by an extra copy of chromosome 21)

Answer

Sickle cell anemia (caused by a mutation in the beta-hemoglobin gene)

Question 19

What is the central dogma of molecular biology?

Accepted Answer

DNA -> RNA -> Protein

Answer

RNA -> DNA -> Protein (Reverse transcription is not a common biological process)

Answer

Protein -> DNA -> RNA (This is not a known biological process)

Answer

Protein -> RNA -> DNA (This is not a known biological process)

Question 20

What is the main function of enhancers in gene regulation?

Accepted Answer

Enhancers enhance transcription rates by binding transcription factors.

Answer

Enhancers directly bind RNA polymerase, initiating transcription.

Answer

Enhancers are exclusively located within introns.

Answer

Enhancers are invariably positioned downstream of the gene they regulate.

Question 21

What is gene expression?

Accepted Answer

Using genetic information to create a protein

Answer

Copying genetic information from DNA to RNA

Answer

Copying genetic information from RNA to protein

Answer

Controlling the activity of genes

Question 22

Which step initiates gene expression?

Accepted Answer

Transcription

Answer

Translation (Translation occurs after transcription)

Answer

Splicing (Splicing occurs after transcription)

Answer

Replication (Replication is not directly involved in gene expression)

Question 23

Which enzyme is essential for transcription?

Accepted Answer

RNA polymerase

Answer

DNA polymerase (Involved in DNA replication)

Answer

Helicase (Involved in DNA replication)

Answer

Ligase (Involved in DNA replication)

Question 24

What process converts the genetic code into a protein?

Accepted Answer

Translation

Answer

Translocation (Not a known biological process)

Answer

Replication (Replication creates new copies of DNA)

Answer

Transcription (Transcription creates RNA from DNA)

Question 25

What is the primary function of ribosomes in gene expression?

Accepted Answer

Protein synthesis

Answer

Transcription initiation (Not a function of ribosomes)

Answer

DNA replication (Not a function of ribosomes)

Answer

Gene regulation (Not a primary function of ribosomes)

Question 26

What is the process of removing non-coding regions from an RNA molecule called?

Accepted Answer

Splicing

Answer

Polyadenylation (Addition of a tail of adenine nucleotides to the 3' end of an RNA molecule)

Answer

Capping (Addition of a cap to the 5' end of an RNA molecule)

Question 27

What is the name of the DNA sequence that signals the start of transcription?

Accepted Answer

Promoter

Answer

Operator (Typically associated with prokaryotic gene regulation)

Answer

Terminator (Signals the end of transcription)

Answer

Enhancer (Enhances transcription but is not essential for initiation)

Question 28

What is the term for a sequence that regulates gene expression from a distance?

Accepted Answer

Enhancer

Answer

Silincer

Answer

Promoter

Answer

Operator