Molecular Biology Quizzes: Test Your Knowledge

Question 1

Which molecular biology technique is used to make multiple copies of a specific DNA region?

Accepted Answer

Polymerase chain reaction (PCR)

Answer

DNA sequencing

Answer

Microarray

Answer

Southern blotting

Question 2

Which technique is commonly used to visualize the expression of specific genes within a cell?

Accepted Answer

In situ hybridization (ISH)

Answer

Polymerase chain reaction (PCR)

Answer

DNA sequencing

Answer

Gel electrophoresis

Question 3

In eukaryotic cells, RNA polymerases I, II, and III have distinct roles in gene transcription. Which of the following is NOT a function of one of these RNA polymerases?

Accepted Answer

Transcription of microRNAs

Answer

Transcription of ribosomal RNA genes

Answer

Transcription of transfer RNA genes

Answer

Transcription of protein-coding genes

Question 4

What is the primary structure of DNA?

Accepted Answer

Double helix of complementary deoxyribonucleotides

Answer

Triple helix of complementary deoxyribonucleotides

Answer

Single strand of deoxyribonucleotides

Answer

Single strand of ribonucleotides

Question 5

Which of the following RNA molecules is NOT found naturally?

Accepted Answer

siRNA

Answer

mRNA

Answer

tRNA

Question 6

Which of the following processes is exclusive to translation and not part of transcription?

Accepted Answer

Amino acid polymerization

Answer

Initiation

Answer

Elongation

Answer

Termination

Question 7

In eukaryotic cells, which RNA polymerase is dedicated to transcribing transfer RNA (tRNA) and other small RNA molecules?

Accepted Answer

RNA polymerase III

Answer

RNA polymerase I

Answer

RNA polymerase II

Answer

RNA polymerase IV

Question 8

In DNA replication, which enzyme plays the primary role in unwinding the two strands of the DNA double helix?

Accepted Answer

DNA helicase

Answer

DNA primase

Answer

DNA ligase

Answer

DNA polymerase

Question 9

Which of the following is not directly involved in the process of protein synthesis?

Accepted Answer

Small nuclear RNA (snRNA)

Answer

Messenger RNA (mRNA)

Answer

Transfer RNA (tRNA)

Answer

Ribosomal RNA (rRNA)

Question 10

Which technique is used to separate DNA fragments based on their size?

Accepted Answer

Gel electrophoresis

Answer

DNA sequencing

Answer

PCR

Answer

Microarrays

Question 11

In the process of transcription, which of the following statements is accurate?

Accepted Answer

RNA polymerase constructs a complementary RNA strand using a DNA template strand during transcription.

Accepted Answer

A specific termination sequence in the DNA template strand signals the end of transcription.

Answer

Transcription takes place in the cytoplasm.

Answer

Transcription is always a two-way process.

Question 12

Which step is NOT part of the transcription process?

Accepted Answer

Splicing

Answer

Initiation

Answer

Elongation

Answer

Termination

Question 13

Which technique is used to make multiple copies of a specific DNA sequence?

Accepted Answer

PCR

Answer

DNA sequencing

Answer

Microarray

Answer

Southern blotting

Question 14

Which RNA molecule is NOT directly involved in translating the genetic code into a chain of amino acids during protein synthesis?

Accepted Answer

Small nuclear RNA (snRNA)

Answer

Messenger RNA (mRNA)

Answer

Transfer RNA (tRNA)

Answer

Ribosomal RNA (rRNA)

Question 15

Which step is NOT part of the transcription process?

Accepted Answer

Translation

Answer

Initiation

Answer

Elongation

Answer

Termination

Question 16

In transcription, what occurs?

Accepted Answer

A complementary RNA molecule is synthesized using the DNA template.

Answer

A complementary DNA molecule is synthesized using the RNA template.

Answer

A complementary protein molecule is synthesized using the RNA template.

Answer

Transcription occurs only in prokaryotic cells.

Question 17

In molecular biology, which technique is primarily used to separate DNA fragments by size?

Accepted Answer

Gel electrophoresis

Answer

Restriction enzyme digestion

Answer

PCR amplification

Answer

DNA sequencing

Question 18

In molecular biology, which technique is specifically employed to amplify a specific DNA region?

Accepted Answer

Polymerase Chain Reaction (PCR)

Answer

DNA Sequencing

Answer

Microarray

Answer

Gel Electrophoresis

Question 19

What is the primary application of polymerase chain reaction (PCR)?

Accepted Answer

Amplifying a specific region of DNA exponentially

Answer

Sequencing nucleotides in a DNA molecule

Answer

Studying the expression of multiple genes simultaneously

Answer

Cutting DNA at specific sequences

Question 20

Which unique structural modification is a characteristic feature of tRNA molecules?

Accepted Answer

Incorporation of pseudouridine

Answer

Presence of a 5' cap

Answer

Attachment of a 3' poly(A) tail

Answer

Inclusion of intron sequences

Question 21

In eukaryotic cells, where does RNA splicing take place?

Accepted Answer

Nucleus

Answer

Cytoplasm

Answer

Ribosome

Answer

Golgi apparatus

Question 22

Which component is NOT a fundamental building block of a nucleotide?

Accepted Answer

Potassium ion

Answer

Phosphate group

Answer

Nitrogenous base (e.g., adenine, cytosine, guanine, or uracil)

Answer

Ribose or deoxyribose sugar

Question 23

Which process is not included in the central dogma of molecular biology?

Accepted Answer

DNA methylation

Answer

DNA replication

Answer

RNA transcription

Answer

Protein translation

Question 24

In the process of gene expression, what primarily determines the sequence of amino acids in a newly synthesized protein?

Accepted Answer

Genetic code in DNA

Answer

Availability of raw materials in the cell

Answer

Environmental conditions

Answer

Concentration of existing proteins in the cell

Question 25

Which type of RNA is NOT directly involved in protein synthesis?

Accepted Answer

Small nuclear RNA (snRNA)

Answer

Messenger RNA (mRNA)

Answer

Transfer RNA (tRNA)

Answer

Ribosomal RNA (rRNA)

Question 26

In transcription, which enzyme plays the primary role in synthesizing the RNA molecule, utilizing the DNA template as a guide?

Accepted Answer

RNA Polymerase

Answer

Helicase

Answer

DNA Polymerase

Answer

Topoisomerase

Question 27

Which enzyme is responsible for unwinding the DNA helix during replication?

Accepted Answer

Helicase

Answer

Ligase

Answer

RNA Polymerase

Answer

Primase

Question 28

During protein synthesis, which ribosomal component interacts with the tRNA's anticodon via hydrogen bonds, enabling the incorporation of a specific amino acid into the growing polypeptide chain?

Accepted Answer

Small subunit's decoding center

Answer

Large subunit's peptidyltransferase center

Answer

Ribosome's exit tunnel

Answer

5' cap of the mRNA molecule

Question 29

In gene expression, which process allows a cell to use the genetic code in mRNA to build a protein?

Accepted Answer

Translation

Answer

Replication

Answer

Transcription

Answer

Mutation

Question 30

In population-based studies, which technique is primarily employed to detect genetic variations?

Accepted Answer

DNA Microarrays

Answer

Polymerase Chain Reaction (PCR)

Answer

Gel Electrophoresis

Answer

DNA Sequencing

Question 31

Which nitrogenous base is absent from DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Guanine

Answer

Cytosine

Question 32

Which mechanism regulates gene accessibility, controlling transcription during gene expression?

Accepted Answer

DNA methylation

Accepted Answer

Histone acetylation

Answer

RNA interference

Answer

MicroRNA

Question 33

What is the defining characteristic of a frameshift mutation?

Accepted Answer

It alters the DNA sequence, potentially changing the amino acid sequence of the encoded protein.

Answer

It substitutes a nucleotide without affecting the protein's amino acid sequence.

Answer

It prematurely ends protein synthesis.

Answer

It exchanges a purine for a pyrimidine or vice versa.

Question 34

In eukaryotic cells, which RNA polymerase is absent?

Accepted Answer

RNA polymerase IV

Answer

RNA polymerase I

Answer

RNA polymerase II

Answer

RNA polymerase III

Question 35

Which technique is specifically designed to amplify specific DNA sequences outside of a living organism?

Accepted Answer

PCR (Polymerase Chain Reaction)

Answer

DNA sequencing

Answer

Microarray analysis

Answer

Gel electrophoresis

Question 36

Which technique is not employed for DNA sequencing?

Accepted Answer

Southern blotting

Answer

Sanger sequencing

Answer

Next-generation sequencing (NGS)

Answer

Pyrosequencing

Question 37

Define 'Operon' and explain its significance in regulating gene expression in prokaryotes.

Accepted Answer

An operon is a cluster of genes transcribed together into a single mRNA molecule, enabling coordinated expression.

Answer

An operon is a DNA region controlling the expression of a single gene.

Answer

An operon is a non-coding RNA regulating gene expression by binding to specific DNA sequences.

Answer

An operon is a protein complex facilitating transcription and translation on DNA.

Question 38

How can molecular biology revolutionize healthcare, especially in the field of personalized medicine?

Accepted Answer

Molecular biology helps identify genetic variations linked to diseases, allowing for the development of tailored therapies.

Answer

Molecular biology's impact on personalized medicine is limited because it mainly studies basic biological processes.

Answer

Personalized medicine relies exclusively on molecular biology techniques like DNA sequencing to guide treatment decisions.

Answer

Personalized medicine based on molecular biology is already widely used in clinical practice with minimal challenges.

Question 39

In the context of gene expression, what is the role of a promoter?

Accepted Answer

Provides a binding site for transcription factors to initiate transcription

Answer

Serves as a template for RNA synthesis

Answer

Signals the termination of transcription

Answer

Regulates the translation of mRNA into proteins

Question 40

What is the primary purpose of a DNA microarray?

Accepted Answer

To detect the presence of specific DNA sequences

Answer

To amplify DNA samples

Answer

To sequence DNA fragments

Answer

To modify DNA molecules

Question 41

What is the name of the process by which DNA is copied into RNA?

Accepted Answer

Transcription

Answer

Translation

Answer

Replication

Answer

Polymerisation

Question 42

What is the primary function of an enzyme in a biological system?

Accepted Answer

To catalyse chemical reactions

Answer

To store genetic information

Answer

To transport substances across membranes

Answer

To provide structural support

Question 43

What is the name of the technique used to separate and visualise DNA fragments?

Accepted Answer

Gel electrophoresis

Answer

PCR

Answer

DNA sequencing

Answer

Microarray

Question 44

Which molecular biology technique is used to make multiple copies of a specific DNA region?

Accepted Answer

PCR (Polymerase Chain Reaction)

Answer

Restriction digestion

Answer

Gel electrophoresis

Answer

DNA sequencing

Question 45

The process by which DNA is transcribed into RNA is known as:

Accepted Answer

Transcription

Answer

Replication

Answer

Translation

Answer

Mutation

Question 46

Which enzyme is responsible for unwinding the DNA double helix during replication?

Accepted Answer

Helicase

Answer

Polymerase

Answer

Ligase

Answer

Topoisomerase

Question 47

The genetic code is considered to be:

Accepted Answer

Triplet

Answer

Duplet

Answer

Quadruplet

Answer

Hexaplet

Question 48

Which technique is used to amplify specific regions of DNA?

Accepted Answer

PCR

Answer

DNA sequencing

Answer

Microarrays

Answer

Gel electrophoresis

Question 49

The process by which RNA is translated into a protein is called:

Accepted Answer

Translation

Answer

Replication

Answer

Transcription

Answer

Mutation

Question 50

Which of the following is NOT a type of RNA molecule?

Accepted Answer

DNA

Answer

mRNA

Answer

tRNA

Answer

rRNA

Question 51

The primary function of a promoter in gene expression is to:

Accepted Answer

Bind RNA polymerase

Answer

Terminate transcription

Answer

Splice mRNA

Answer

Translate mRNA

Question 52

The Human Genome Project was a groundbreaking scientific endeavor that resulted in:

Accepted Answer

The sequencing of the entire human genome

Answer

The discovery of all human genes

Answer

The development of personalized medicine

Answer

The cure for all genetic diseases

Question 53

Which nitrogenous base is NOT found in DNA?

Accepted Answer

Uracil

Answer

Adenine

Answer

Thymine

Answer

Cytosine

Question 54

What is the enzyme primarily responsible for unwinding the DNA double helix during replication?

Accepted Answer

Helicase

Answer

Polymerase

Answer

Ligase

Answer

Restriction endonuclease

Question 55

Which molecular biology technique is used to amplify a specific DNA sequence?

Accepted Answer

Polymerase Chain Reaction (PCR)

Answer

DNA sequencing

Answer

Microarray

Answer

Gel electrophoresis

Question 56

What is the primary function of ribosomes in protein synthesis?

Accepted Answer

Translating mRNA into proteins

Answer

Storing genetic information

Answer

Catalyzing chemical reactions

Answer

Regulating cell division

Question 57

Which type of RNA molecule plays a regulatory role in gene expression?

Accepted Answer

MicroRNA

Answer

Transfer RNA

Answer

Ribosomal RNA

Answer

Messenger RNA

Question 58

State the central dogma of molecular biology.

Accepted Answer

DNA is transcribed to mRNA, which is translated to proteins

Answer

Proteins are transcribed to mRNA, which is translated to DNA

Answer

RNA is transcribed to proteins, which are translated to DNA

Answer

DNA is translated to proteins, which are transcribed to RNA

Question 59

What is the significance of stem cells in molecular biology research?

Accepted Answer

They can differentiate into various cell types

Answer

They are resistant to genetic modifications

Answer

They have an infinite lifespan

Answer

They are exclusively found in embryos

Question 60

Identify the enzyme responsible for unwinding the DNA helix during replication?

Accepted Answer

Helicase

Answer

DNA polymerase

Answer

DNA ligase

Answer

RNA polymerase

Question 61

What is the primary function of a promoter in gene expression?

Accepted Answer

Binding RNA polymerase and initiating transcription

Answer

Terminating transcription

Answer

Splicing mRNA

Answer

Translating mRNA into protein

Question 62

Which technique amplifies specific DNA sequences?

Accepted Answer

PCR

Answer

DNA sequencing

Answer

Microarray

Answer

Southern blotting

Question 63

Which amino acid corresponds to the codon UGU?

Accepted Answer

Cysteine

Answer

Alanine

Answer

Asparagine

Answer

Glycine

Question 64

Differentiate between a silent and a missense mutation.

Accepted Answer

Silent mutations do not change the amino acid sequence, while missense mutations do

Answer

Silent mutations change the amino acid sequence, while missense mutations do not

Answer

Silent mutations occur in introns, while missense mutations occur in exons

Answer

Missense mutations are more common than silent mutations