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

Ribosome is made up of ______.

  1. RNA and protein

  2. protein only

  3. RNA only

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

Ribosomes are cellular structures composed of ribosomal RNA (rRNA) and proteins. They are the sites of protein synthesis in the cell.

Multiple choice

Which of the following statements is FALSE?

  1. The anticodon is a sequence of three base pairs on tRNA that is complementary to the matching three base pairs on mRNA.

  2. The termination codon is a nucleotide triplet within tRNA that signals termination of translation.

  3. The start codon always codes for methionine in eukaryotes.

  4. The most common start codon is AUG.

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The stop codon or termination codon is a nucleotide triplet within mRNA that signals a termination of translation.

Multiple choice

In a virus, the RNA genome covering protein is:

  1. G Protein

  2. M protein

  3. L protein

  4. N protein

  5. Gag-onc fusion protein
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the major structural protein and covers the RNA genome. It protects the genome from nucleases and holds it in a conformation that allows transcription.

Multiple choice

Which of the following is a pair of RNA databases?

  1. RDP and SILVA

  2. RDP and EuroCarbDB

  3. EuroCarbDB and SILVA

  4. Reactome and SILVA

  5. RDP and Reactome
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

RDP provides quality-controlled, aligned and annotated Bacterial and Archaeal 16S rRNA sequences and Fungal 28S rRNA sequences and a suite of analysis tools to the scientific community. SILVA provides comprehensive, quality checked and regularly updated datasets of aligned small (16S/18S, SSU) and large subunit (23S/28S, LSU) ribosomal RNA (rRNA) sequences for all three domains of life (Bacteria, Archaea and Eukarya).

Multiple choice

What is the difference between SER and RER?

  1. Antolysis

  2. Presence of DNA

  3. Presence of RNA

  4. Presence of ribosomes

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Rough endoplasmic reticulum (RER) is studded with ribosomes on its surface, which gives it a rough appearance and makes it active in protein synthesis. Smooth endoplasmic reticulum (SER) lacks ribosomes.

Multiple choice

Which of the following is/are stop codon(s)?

  1. Opal

  2. Ochre

  3. Amber

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

Opal (UGA), Ochre (UAA), and Amber (UAG) are all standard stop codons in the genetic code. Therefore, all of the listed options are correct.

Multiple choice

Rho protein helps in

  1. transcription termination

  2. translation

  3. RNA processing

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

The Rho protein is a bacterial protein that binds to the nascent RNA transcript and facilitates the termination of transcription by causing the RNA polymerase to dissociate from the DNA template.

Multiple choice

RNA polymerase has 5 subunits in prokaryotes. They are

  1. 2 á subunits, 1 â subunit, 1 â' subunit, and 1 ù subunit

  2. 1 â subunits, 1 á subunit, 1 á' subunit, and 1 ù subunit

  3. 2 á subunits,2 â subunit, 1 â' subunit, and 1 ì subunit

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

The core RNA polymerase enzyme in prokaryotes consists of five subunits: two alpha (a) subunits, one beta (b) subunit, one beta-prime (b') subunit, and one omega (w) subunit.

Multiple choice

Which of the following statements is/are CORRECT?

  1. DNA microarrays are used to measure the concentration of different tRNAs in a biological sample.
  2. The complete set of sRNAs that are transcribed in a cell is often called its transcriptome.
  3. Expressed sequence tags (ESTs) are short, single-read mRNA sequences.

  1. Only 1

  2. Only 2

  3. Only 3

  4. All of these

  5. None of these
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

All are incorrect, hence this is correct answer. DNA microarrays are used to measure the concentration of different mRNAs in a biological sample. The complete set of mRNAs that are transcribed in a cell is often called its transcriptome. Expressed sequence tags (ESTs) are short, single-read cDNA sequences.