Question

Which of the classes of RNA molecules is never found in the cytosol?

• A. Ribosomal RNA
• B. Transfer RNA
• C. Messenger RNA
• D. Primary mRNA transcript

Answer 1

The correct option is D Primary mRNA transcript

All the RNAs have different functions to perform in the cell and nucleus. Ribosomal RNA is present in the cytoplasm near ribosomes, they help in the formation of larger and smaller subunits of ribosomes and also helps in the formation of proteins in the process of translation. The messenger RNA helps to carry the genetic information from the nucleus to the cell and are present in the cytoplasm. Transfer RNA also helps in the process of protein synthesis and is present in the cytoplasm. A primary mRNA transcript is a premature mRNA formes at the time of transcription by DNA. Later these are modified at the time of translation.

So, the correct option is ' Primary mRNA transcript'.