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 of the following is the first event in eukaryotic translation process during the binding of the mRNA leader sequence?

  1. Binding of the mRNA leader to the smaller ribosomal subunit

  2. Binding of the mRNA leader to the larger ribosomal subunit

  3. Binding of the mRNA leader to the polysome core

  4. Binding of the mRNA leader to the rRNA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In eukaryotic translation process, during the binding of the mRNA leader sequence, the first event is the binding of the mRNA leader to the smaller ribosomal subunit.

Multiple choice

Which of the following does not define the transcription unit in a DNA?

  1. Terminator

  2. Promoter

  3. Intron

  4. Structural gene

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

Yes, it is correct. Introns are non-coding sections of an RNA transcript, or the DNA encoding it, which are spliced out before the RNA molecule is translated into a protein. The sections of DNA (or RNA) that code for proteins are called exons.

Multiple choice

A cDNA library contains clones representing which of the following?

  1. Micro RNA (miRNA)

  2. mRNA

  3. Genomic DNA

  4. Exon

  5. Introns
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The messenger RNA (mRNA), molecule in cells that carries codes from the DNA in the nucleus to the sites of protein synthesis in the cytoplasm (the ribosomes). cDNA library is created by reverse transcription of mRNA.

Multiple choice

Which of the following algorithms requires the user to provide a pairwise or multiple alignment as input?

  1. RNAalifold
  2. Foldalign
  3. Dynalign

  1. Only 1

  2. Only 2

  3. Only 3

  4. 1 and 2

  5. 2 and 3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Algorithms That Use Prealignment This type of algorithm requires the user to provide a pairwise or multiple alignment as input. The sequence alignment can be obtained using standard alignment programs such as T-Coffee, PRRN, or Clustal. RNAalifold is a program in the Vienna package. It uses a multiple sequence alignment as input to analyze covariation patterns on the sequences.

Multiple choice

.................................... is a manually curated database of eukaryotic transcription factors, their genomic binding sites and DNA binding profiles.

  1. TRANSFAC

  2. PRINTS

  3. PAZAR

  4. TRRD

  5. BRENDA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

TRANSFAC (TRANScription FACtor database) is a manually curated database of eukaryotic transcription factors, their genomic binding sites and DNA binding profiles. The contents of the database can be used to predict potential transcription factor binding sites.

Multiple choice

Which of the following statements is FALSE?

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

  2. The most common start codon is AUG.

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

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

  5. All are true.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

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