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 is the sequence of nucleotides in the RNA transcript complementary to?

  1. The sequence of nucleotides in the coding strand of DNA

  2. The sequence of nucleotides in the non-coding strand of DNA

  3. The sequence of nucleotides in the RNA polymerase

  4. The sequence of nucleotides in the ribosome
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The RNA transcript is complementary to the sequence of nucleotides in the non-coding strand of DNA.

Multiple choice

What is the role of the promoter in transcription?

  1. It signals the start of transcription

  2. It signals the end of transcription

  3. It helps RNA polymerase bind to the DNA

  4. It helps RNA polymerase move along the DNA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The promoter is a region of DNA that signals the start of transcription.

Multiple choice

What is the role of the terminator in transcription?

  1. It signals the start of transcription

  2. It signals the end of transcription

  3. It helps RNA polymerase bind to the DNA

  4. It helps RNA polymerase move along the DNA
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The terminator is a region of DNA that signals the end of transcription.

Multiple choice

What is the process by which RNA polymerase moves along the DNA during transcription called?

  1. Elongation

  2. Initiation

  3. Termination

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

Elongation is the process by which RNA polymerase moves along the DNA during transcription.

Multiple choice

What is the role of proofreading in transcription?

  1. It helps RNA polymerase bind to the DNA

  2. It helps RNA polymerase move along the DNA

  3. It corrects errors in the RNA transcript

  4. It helps RNA polymerase terminate transcription
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Proofreading is a process by which RNA polymerase corrects errors in the RNA transcript.

Multiple choice

What is the name of the RNA molecule that is transcribed from the promoter region of a gene?

  1. Messenger RNA (mRNA)

  2. Transfer RNA (tRNA)

  3. Ribosomal RNA (rRNA)

  4. Small nuclear RNA (snRNA)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The RNA molecule that is transcribed from the promoter region of a gene is called small nuclear RNA (snRNA).

Multiple choice

What is the function of messenger RNA (mRNA)?

  1. It carries the genetic code from the nucleus to the ribosome

  2. It helps RNA polymerase bind to the DNA

  3. It helps RNA polymerase move along the DNA

  4. It corrects errors in the RNA transcript
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Messenger RNA (mRNA) carries the genetic code from the nucleus to the ribosome.

Multiple choice

What is the function of transfer RNA (tRNA)?

  1. It brings amino acids to the ribosome

  2. It helps RNA polymerase bind to the DNA

  3. It helps RNA polymerase move along the DNA

  4. It corrects errors in the RNA transcript
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Transfer RNA (tRNA) brings amino acids to the ribosome.

Multiple choice

What is the function of ribosomal RNA (rRNA)?

  1. It forms the structure of the ribosome

  2. It helps RNA polymerase bind to the DNA

  3. It helps RNA polymerase move along the DNA

  4. It corrects errors in the RNA transcript
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ribosomal RNA (rRNA) forms the structure of the ribosome.

Multiple choice

What is the function of small nuclear RNA (snRNA)?

  1. It helps splice introns out of pre-mRNA

  2. It helps RNA polymerase bind to the DNA

  3. It helps RNA polymerase move along the DNA

  4. It corrects errors in the RNA transcript
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Small nuclear RNA (snRNA) helps splice introns out of pre-mRNA.

Multiple choice

What is the name of the process by which introns are removed from pre-mRNA?

  1. Splicing

  2. Capping

  3. Polyadenylation

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

Splicing is the process by which introns are removed from pre-mRNA.

Multiple choice

What is the name of the process by which a 5' cap is added to pre-mRNA?

  1. Splicing

  2. Capping

  3. Polyadenylation

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

Capping is the process by which a 5' cap is added to pre-mRNA.

Multiple choice

What is the primary function of tRNA in the process of translation?

  1. To carry amino acids to the ribosome

  2. To decode the genetic information in mRNA

  3. To form peptide bonds between amino acids

  4. To release the newly synthesized protein from the ribosome
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

tRNA molecules are responsible for bringing specific amino acids to the ribosome, based on the sequence of codons in the mRNA.

Multiple choice

What is the role of the ribosome in translation?

  1. To assemble amino acids into a polypeptide chain

  2. To proofread the sequence of amino acids in the protein

  3. To release the newly synthesized protein from the tRNA

  4. To transport mRNA from the nucleus to the cytoplasm
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The ribosome is a complex structure that catalyzes the formation of peptide bonds between amino acids, resulting in the assembly of a polypeptide chain.

Multiple choice

What is the sequence of events that occurs during translation?

  1. Initiation, Elongation, Termination

  2. Transcription, Translation, Replication

  3. Glycolysis, Krebs Cycle, Electron Transport Chain

  4. Mitosis, Meiosis, Fertilization
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Translation involves three main stages: initiation, elongation, and termination. During initiation, the ribosome binds to the mRNA and the start codon. Elongation involves the sequential addition of amino acids to the growing polypeptide chain. Termination occurs when a stop codon is encountered, signaling the release of the newly synthesized protein.