In prokaryotic cells, control of gene expression primarily occurs at which level?

• A. Post-translational level
• B. Transcriptional level
• C. Epigenetic level
• D. Translational level

Answer: (B)

Verified step by step guidance

1. Understand the concept of gene expression: Gene expression is the process by which information from a gene is used to synthesize a functional gene product, usually a protein.
2. Identify the levels of gene expression control: Gene expression can be regulated at various stages, including transcriptional, post-transcriptional, translational, and post-translational levels.
3. Focus on prokaryotic cells: In prokaryotes, the primary control of gene expression occurs at the transcriptional level, where the synthesis of mRNA from DNA is regulated.
4. Consider the mechanisms involved: Transcriptional regulation in prokaryotes often involves operons, which are clusters of genes under the control of a single promoter, allowing coordinated regulation.
5. Recognize the importance of transcriptional control: By controlling transcription, prokaryotic cells efficiently manage resource allocation and respond to environmental changes, making it the primary level of gene expression regulation.