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

What enzyme is responsible for catalyzing 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 the synthesis of RNA from a DNA template.

Multiple choice

What is the direction of transcription?

  1. 5' to 3'

  2. 3' to 5'

  3. Bidirectional

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

Transcription proceeds in the 5' to 3' direction, meaning that the RNA molecule is synthesized from the 5' end to the 3' end.

Multiple choice

What is the structure of RNA?

  1. Single-stranded

  2. Double-stranded

  3. Linear

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

RNA is typically single-stranded, unlike DNA, which is double-stranded.

Multiple choice

What is the role of RNA in gene regulation?

  1. RNA interference (RNAi)

  2. MicroRNAs (miRNAs)

  3. Long non-coding RNAs (lncRNAs)

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

RNA plays a role in gene regulation through various mechanisms, including RNA interference (RNAi), microRNAs (miRNAs), and long non-coding RNAs (lncRNAs).

Multiple choice

What is the role of RNA in splicing?

  1. Removal of introns

  2. Addition of exons

  3. Joining of exons

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

RNA plays a role in splicing, which involves the removal of introns (non-coding regions), the addition of exons (coding regions), and the joining of exons to form a mature mRNA molecule.

Multiple choice

What is the role of RNA in translation?

  1. Carrying the genetic code to the ribosome

  2. Binding to tRNA molecules

  3. Positioning amino acids in the correct order

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

RNA plays a crucial role in translation, which involves carrying the genetic code to the ribosome, binding to tRNA molecules, and positioning amino acids in the correct order to form a protein.

Multiple choice

What is the role of RNA in viral replication?

  1. Serving as the genetic material of some viruses

  2. Encoding viral proteins

  3. Packaging viral particles

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

RNA plays a vital role in viral replication, serving as the genetic material of some viruses, encoding viral proteins, and participating in the packaging of viral particles.

Multiple choice

What is the role of RNA in cancer?

  1. Promoting tumor growth

  2. Suppressing tumor growth

  3. Both promoting and suppressing tumor growth

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

RNA can play both oncogenic (tumor-promoting) and tumor-suppressing roles in cancer, depending on the specific RNA molecule and cellular context.

Multiple choice

What is the role of RNA in neurodegenerative diseases?

  1. Aggregation of RNA molecules

  2. Dysregulation of RNA metabolism

  3. Both aggregation of RNA molecules and dysregulation of RNA metabolism

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In neurodegenerative diseases, both aggregation of RNA molecules and dysregulation of RNA metabolism have been implicated in disease pathogenesis.

Multiple choice

What is the structure that carries genetic information in cells?

  1. Gene

  2. Chromosome

  3. DNA

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

Chromosomes are structures in the nucleus of cells that carry genetic information in the form of DNA.

Multiple choice

What is the term for a change in the DNA sequence?

  1. Mutation

  2. Recombination

  3. Transcription

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

Mutation is a change in the DNA sequence.

Multiple choice

What is the term for the process of making RNA from DNA?

  1. Mutation

  2. Recombination

  3. Transcription

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

Transcription is the process of making RNA from DNA.

Multiple choice

What is the term for the process of making proteins from RNA?

  1. Mutation

  2. Recombination

  3. Transcription

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

Translation is the process of making proteins from RNA.

Multiple choice

What is the RNA world hypothesis?

  1. The hypothesis that RNA was the first genetic material on Earth

  2. The hypothesis that RNA was the first self-replicating molecule on Earth

  3. The hypothesis that RNA was the first molecule to evolve on Earth

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The RNA world hypothesis proposes that RNA was the first genetic material on Earth, the first self-replicating molecule on Earth, and the first molecule to evolve on Earth.

Multiple choice

What is the evidence supporting the RNA world hypothesis?

  1. The discovery of ribozymes

  2. The presence of RNA in all living cells

  3. The ability of RNA to replicate itself

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Evidence supporting the RNA world hypothesis includes the discovery of ribozymes, which are RNA molecules that can catalyze chemical reactions, the presence of RNA in all living cells, and the ability of RNA to replicate itself.