Question

Which of the classes of RNA molecules is found in almost no prokaryotes?

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

Answer 1

Answer: (D)

Primary mRNA transcript

Ribosomal RNA (rRNA), transfer RNA (tRNA) and messenger RNA (mRNA) are all found in both eukaryotes and prokaryotes. However in eukaryotes after transcription, the primary mRNA transcript is found which contains both introns and exons. Introns are removed by a process known as splicing and after undergoing two other processes capping, tailing primary transcript mRNA is transformed into mature functional mRNA.

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