Question

All of the following are found in prokaryotic mRNA except

• A. AUG
• B. UGA codon
• C. introns
• D. uracil

Answer 1

The correct option is C introns

Prokaryotes have no nucleus, and the genetic material (DNA) is less organized in chromatin and chromosomes than it is in eukaryote unicellulars. They have ribosomes and cytoplasmic satellite DNA and cytoskeleton, but lack membrane-bound organelles such as plastids and mitochondria.

Eukaryotes harbor introns in the genomic structure, whereas no prokaryotes identified so far carry introns.

Introns are non-functional gene sequences that are removed by a process called splicing post transcriptionin eukaryotes. AUG is the most common START codon and it codes for the amino acid methionine (Met) in eukaryotes and formyl methionine (fMet) in prokaryotes. Codon UGA in an mRNA indicates translation termination. Messenger RNA is a single stranded structure, with no base pairing. It contains bases such as adenine, guanine, cytosine and uracil.