NEETZoologyMolecular Basis of Inheritance
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In eukaryotes, the 5S rRNA is transcribed by RNA polymerase III. Reason (R): RNA polymerase I is responsible for the transcription of 28S, 18S, and 5.8S rRNAs. In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Step-by-step solution
According to the division of labor in eukaryotic transcription, RNA polymerase III is responsible for the transcription of tRNA, 5S rRNA, and snRNAs. Thus, the Assertion is correct. RNA polymerase I transcribes the major ribosomal RNAs, which are 28S, 18S, and 5.8S rRNAs. Thus, the Reason is also correct. However, the Reason does not explain why RNA polymerase III transcribes 5S rRNA; it merely states an independent fact regarding the function of RNA polymerase I. Therefore, both (A) and (R) are correct but (R) is