Molecular Biology Learning Quizzes | Chemistry | Bachelor of Science in Mechanical Engineering

Question 1

Which of the following is a characteristic of a mutation?

Accepted Answer

A change in the DNA sequence

Answer

A change in the number of chromosomes

Answer

A change in the structure of a protein

Answer

A change in gene expression levels

Question 2

What is the relationship between a codon and an anticodon?

Accepted Answer

A codon is a sequence of three nucleotides in DNA, and an anticodon is a complementary sequence in tRNA.

Answer

An anticodon is a sequence of three nucleotides in DNA, and a codon is a complementary sequence in mRNA.

Answer

A codon is a sequence of three nucleotides in mRNA, and an anticodon is a complementary sequence in DNA.

Answer

A codon is a sequence of three nucleotides in tRNA, and an anticodon is a complementary sequence in rRNA.

Question 3

The correct sequence of steps in protein synthesis is:

Accepted Answer

Replication, transcription, translation

Answer

Transcription, translation, replication

Answer

Translation, transcription, replication

Answer

Replication, translation, transcription

Question 4

In protein synthesis, the ribosome functions to:

Accepted Answer

Translate the mRNA code into a polypeptide chain

Answer

Unwind the DNA double helix

Answer

Transcribe the DNA code into a complementary mRNA strand

Answer

Replicate the DNA molecule

Question 5

Which component forms the structural unit of DNA?

Accepted Answer

Nucleotide

Answer

Amino acid

Answer

Sugar-phosphate backbone

Answer

Hydrogen bond

Question 6

The mRNA's primary role in protein synthesis is to:

Accepted Answer

Convey genetic information from the nucleus to the ribosome

Answer

Act as a template for protein synthesis

Answer

Transport amino acids to the growing polypeptide chain

Answer

Unwind the DNA double helix

Question 7

The genetic code refers to:

Accepted Answer

The rules that determine which amino acids correspond to each codon

Answer

The sequence of nucleotides in a DNA or RNA molecule

Answer

The physical structure of a DNA or RNA molecule

Answer

The chemical composition of a DNA or RNA molecule

Question 8

In DNA, a promoter is distinct from a terminator because it:

Accepted Answer

Signals the start of a gene, while a terminator signals its end

Answer

Regulates gene expression, while a terminator does not

Answer

Is found only in prokaryotes, while a terminator is found only in eukaryotes

Answer

There is no difference between a promoter and a terminator

Question 9

In eukaryotic genes, introns serve to:

Accepted Answer

Be removed from the mRNA before translation

Answer

Encode proteins

Answer

Regulate gene expression

Answer

Protect the DNA from damage

Question 10

What is the primary function of RNA polymerase in molecular biology?

Accepted Answer

Transcribes DNA into mRNA

Answer

Translates mRNA into proteins

Answer

Replicates DNA

Answer

Regulates gene expression

Question 11

Which technique is commonly used to amplify DNA fragments?

Accepted Answer

PCR

Answer

Gel electrophoresis

Answer

Southern blotting

Answer

DNA sequencing

Question 12

Which of the following is an example of a non-coding RNA molecule?

Accepted Answer

snRNA

Answer

mRNA

Answer

tRNA

Answer

rRNA

Question 13

State the core principle of the central dogma of molecular biology.

Accepted Answer

DNA is transcribed into RNA, which is then translated into proteins

Answer

DNA is translated into proteins, which are then transcribed into RNA

Answer

RNA is transcribed into DNA, which is then translated into proteins

Answer

Proteins are translated into RNA, which is then transcribed into DNA

Question 14

Which of the following sequences represents the increasing complexity of protein structure, starting with the simplest and ending with the most complex?

Accepted Answer

Primary, Secondary, Tertiary, Quaternary

Answer

Quaternary, Primary, Secondary, Tertiary

Answer

Secondary, Primary, Tertiary, Quaternary

Question 15

Which exception to the central dogma involves RNA as the genetic material, and reverse transcriptase enzyme converting it into DNA?

Accepted Answer

Retroviruses

Answer

Prions

Answer

Telomerase

Answer

Somatic cell nuclear transfer

Question 16

Which enzyme is primarily responsible for synthesizing new DNA strands during DNA replication?

Accepted Answer

DNA polymerase

Answer

Ligase

Answer

Helicase

Answer

RNA polymerase

Question 17

What is the primary role of tRNA molecules in the process of protein synthesis?

Accepted Answer

To carry specific amino acids to the ribosome for incorporation into the growing polypeptide chain

Answer

To unwind the DNA double helix during replication

Answer

To catalyze the formation of peptide bonds between amino acids

Answer

To transcribe DNA into mRNA

Question 18

Which type of genetic alteration involves a change in a single nucleotide within a gene?

Accepted Answer

Point mutation

Answer

Translocation

Answer

Insertion

Answer

Deletion

Question 19

The central dogma of molecular biology describes the fundamental flow of genetic information in biological systems.

Accepted Answer

DNA → RNA → Protein

Answer

Protein → RNA → DNA

Answer

RNA → DNA → Protein

Answer

DNA → Protein → RNA

Question 20

Which technique separates DNA fragments based on their size and charge through an agarose gel matrix?

Accepted Answer

Gel electrophoresis

Answer

DNA sequencing

Answer

Polymerase chain reaction (PCR)

Question 21

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

Accepted Answer

To provide a specific binding site for RNA polymerase, thereby initiating transcription

Answer

To terminate transcription

Answer

To translate mRNA into protein

Answer

To splice mRNA

Question 22

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

Accepted Answer

rProtein

Answer