Target Exam

CUET

Subject

Biology

Chapter

Molecular Basis of Inheritance

Question:

Match List-I with List-II

List-I Terms related to RNA

List-II Features

(A). Capping

(I). Transcribes rRNAS

(B). Polyadenylation

(II). Removal of introns

(C). RNA polymerase I

(III). 5' end-methyl guanosine triphosphate addition

(D). Splicing

(IV). Addition of 200-300 adenylate residues

Choose the correct answer from the options given below.

Options:

(A)-(I), (B)-(II), (C)-(III), (D)-(IV)

(A)-(I), (B)-(III), (C)-(II), (D)-(IV)

(A)-(I), (B)-(II), (C)-(IV), (D)-(III)

(A)-(III), (B)-(IV), (C)-(I), (D)-(II)

Correct Answer:

(A)-(III), (B)-(IV), (C)-(I), (D)-(II)

Explanation:

The correct answer is Option (4) → (A)-(III), (B)-(IV), (C)-(I), (D)-(II)

List-I Terms related to RNA

List-II Features

(A). Capping

(III). 5' end-methyl guanosine triphosphate addition

(B). Polyadenylation

(IV). Addition of 200-300 adenylate residues

(C). RNA polymerase I

(I). Transcribes rRNAS

(D). Splicing

(II). Removal of introns

In eukaryotes, there are two additional complexities – (i) 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). (ii) The second complexity is that the primary transcripts contain both the exons and the introns and are non-functional. Hence, it is subjected to a process called splicing where the introns are removed and exons are joined in a defined order. hnRNA undergoes additional processing called as capping and tailing. In capping an unusual nucleotide (methyl guanosine triphosphate) is added to the 5'-end of hnRNA. In tailing, adenylate residues (200-300) are added at 3'-end (polyadenylation) in a template independent manner. It is the fully processed hnRNA, now called mRNA, that is transported out of the nucleus for translation