Question

Regulation of gene expression occurs at ________ level(s) in eukaryotes. Whereas in prokaryotes it occurs in the ________ level

• A. multiple, transcriptional
• B. multiple, translational
• C. single, transcriptional
• D. single, translational

Answer 1

The correct option is A multiple, transcriptional

The process by which information from a gene is used to synthesize proteins is called gene expression.
The protein is to be synthesised as per the requirement of the cell. Thus depending upon the requirement, switching on or off of the gene occurs. This mechanism is called gene regulation.

In eukaryotes, gene regulation occurs at multiple levels. Following are the levels at which the gene is regulated:
1. Transcriptional level - the stage at which the primary transcript is formed
2.Processing level - during the splicing process
3.When mRNA is transported from nucleus to cytoplasm
4.Translational level - the stage at which mRNA is translated into proteins

In prokaryotes, the regulation of gene expression occurs primarily at the transcriptional level. This is because unlike eukaryotes, in prokaryotes the transcription and tranlsation process almost occur simultaneously. Also, prokaryotes lack nucleus. Thus there is no separate stage where the mRNA is transported from nucleus to cytoplasm.