Biology

Molecular Genetics

917 Questions

Molecular genetics explores the mechanisms of genetic information transfer, including DNA replication, transcription, and translation. It is a core component of biology syllabi. These concepts frequently appear in general science sections of major competitive exams.

DNA replicationTranscription processTranslation processRNA typesCentral dogma

Molecular Genetics Questions

Multiple choice

Which type of gene regulation involves the modification of histones to alter the accessibility of DNA to transcription factors?

  1. Transcriptional regulation

  2. Translational regulation

  3. Post-translational regulation

  4. Epigenetic regulation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Epigenetic regulation involves the modification of histones to alter the accessibility of DNA to transcription factors. This can lead to changes in gene expression without altering the underlying DNA sequence.

Multiple choice

Which type of gene regulation involves the degradation of mRNA molecules to prevent their translation into proteins?

  1. Transcriptional regulation

  2. Translational regulation

  3. Post-translational regulation

  4. Gene silencing
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Translational regulation involves the degradation of mRNA molecules to prevent their translation into proteins. This can be achieved through various mechanisms, such as the binding of microRNAs to mRNA or the phosphorylation of translation initiation factors.

Multiple choice

Which type of gene regulation involves the modification of proteins after they have been translated from mRNA?

  1. Transcriptional regulation

  2. Translational regulation

  3. Post-translational regulation

  4. Gene silencing
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Post-translational regulation involves the modification of proteins after they have been translated from mRNA. This can include modifications such as phosphorylation, glycosylation, or ubiquitination, which can affect the protein's activity, stability, or localization.

Multiple choice

Which type of gene regulation involves the silencing of gene expression through mechanisms such as DNA methylation or histone modification?

  1. Transcriptional regulation

  2. Translational regulation

  3. Post-translational regulation

  4. Gene silencing
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Gene silencing involves the silencing of gene expression through mechanisms such as DNA methylation or histone modification. This can lead to the complete or partial inhibition of gene transcription or translation.

Multiple choice

Which cellular process is responsible for the assembly of ribosomes?

  1. Transcription

  2. Translation

  3. Replication

  4. Ribosome biogenesis
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ribosome biogenesis is the cellular process responsible for the assembly of ribosomes, which are essential for protein synthesis.

Multiple choice

What is the central dogma of molecular biology?

  1. DNA makes RNA makes protein.

  2. RNA makes DNA makes protein.

  3. Protein makes DNA makes RNA.

  4. DNA makes protein makes RNA.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The central dogma of molecular biology states that DNA is transcribed into RNA, which is then translated into protein.

Multiple choice

What is the structure of RNA?

  1. A double helix.

  2. A single helix.

  3. A triple helix.

  4. A quadruple helix.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

RNA is a single helix, meaning that it consists of only one strand of nucleotides.

Multiple choice

What is the process by which DNA is transcribed into RNA?

  1. Transcription.

  2. Translation.

  3. Replication.

  4. Mutation.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Transcription is the process by which DNA is transcribed into RNA.

Multiple choice

What is the enzyme that catalyzes transcription?

  1. RNA polymerase.

  2. DNA polymerase.

  3. Helicase.

  4. Ligase.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

RNA polymerase is the enzyme that catalyzes transcription.

Multiple choice

What is the process by which RNA is translated into protein?

  1. Transcription.

  2. Translation.

  3. Replication.

  4. Mutation.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Translation is the process by which RNA is translated into protein.

Multiple choice

What is the enzyme that catalyzes translation?

  1. Ribosome.

  2. Transfer RNA.

  3. Messenger RNA.

  4. Aminoacyl tRNA synthetase.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The ribosome is the enzyme that catalyzes translation.

Multiple choice

What is the role of tRNA in translation?

  1. It carries amino acids to the ribosome.

  2. It binds to the mRNA.

  3. It catalyzes the formation of peptide bonds.

  4. It releases the newly synthesized protein.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

tRNA carries amino acids to the ribosome.

Multiple choice

What is the role of mRNA in translation?

  1. It carries amino acids to the ribosome.

  2. It binds to the tRNA.

  3. It catalyzes the formation of peptide bonds.

  4. It releases the newly synthesized protein.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

mRNA binds to the tRNA.

Multiple choice

What is the role of the ribosome in translation?

  1. It carries amino acids to the ribosome.

  2. It binds to the mRNA.

  3. It catalyzes the formation of peptide bonds.

  4. It releases the newly synthesized protein.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ribosome catalyzes the formation of peptide bonds.

Multiple choice

What is the role of aminoacyl tRNA synthetase in translation?

  1. It carries amino acids to the ribosome.

  2. It binds to the mRNA.

  3. It catalyzes the formation of peptide bonds.

  4. It releases the newly synthesized protein.
Reveal answer Fill a bubble to check yourself
Correct answer
Explanation

Aminoacyl tRNA synthetase attaches amino acids to tRNA.