Question

Mark the correct statement.

• A. mRNA is polycistronic in eukaryotes and monocistronic in prokaryotes.
• B. mRNA is polycistronic in prokaryotes and monocistronic in eukaryotes.
• C. mRNA is polycistronic in both eukaryotes and prokaryotes.
• D. mRNA is monocistronic in both eukaryotes and prokaryotes.

Answer 1

Answer: (B)

When a particular gene codes for a $mRNA$ strand, it is said to be monocistronic or monogenic. When several genes (cistrons) are transcribed into a single $mRNA$ molecule, it is described as polycistronic or polygenic. Monocistronic $mRNA$ codes for one complete protein molecule while polycistronic $mRNA$ codes for a number of protein molecules. Eukaryotic $mRNA$ is usually monocistronic. Polycistronic $mRNA$ is more common in prokaryotes.