Target Exam

CUET

Subject

Biology

Chapter

Molecular Basis of Inheritance

Question:

How many RNA polymerases are present in the process of transcription in eukaryotes nucleus ?

Options:

2

3

4

5

Correct Answer:

3

Explanation:

The correct answer is Option (2) → 3

In eukaryotes, there are at least three RNA polymerases in the nucleus (in addition to the RNA polymerase found in the organelles). There is a clear cut division of labour. The RNA polymerase I transcribes rRNAs (28S, 18S, and 5.8S), whereas the RNA polymerase III is responsible for transcription of tRNA, 5srRNA, and snRNAs (small nuclear RNAs). The RNA polymerase II transcribes precursor of mRNA, the heterogeneous nuclear RNA (hnRNA).