Which of the following is true about operons?

• A. They allow the organism the opportunity to simultaneously regulate transcription of multiple genes.
• B. They allow the organism the opportunity to regulate transcription of a single gene.
• C. They allow many genes to be expressed at the same time, even those unrelated in function.
• D. They significantly increase the rate of DNA replication, thereby make transcription more efficient.

Answer: (A)

Verified step by step guidance

1. Understand the concept of an operon: An operon is a cluster of genes under the control of a single promoter, allowing coordinated regulation of gene expression.
2. Recognize the function of operons: They enable the simultaneous regulation of multiple genes that are typically related in function, such as those involved in a metabolic pathway.
3. Identify the mechanism of regulation: Operons can be regulated by repressors or activators that bind to the operator region, affecting the transcription of all genes within the operon.
4. Distinguish operons from single gene regulation: Unlike single gene regulation, operons provide a mechanism to control several genes together, not just one.
5. Clarify misconceptions: Operons do not increase the rate of DNA replication; their primary role is in transcription regulation, not replication.