Question

Operons are switched on/off by ____.

Answer 1

Answer: operator

Operons are the functioning units of a gene within a certain DNA segment. The operator within an operon represents a DNA segment to which an activated repressor protein binds to. When this occurs, the transcription is prevented.  

By controlling the operon, an organism is capable of regulation the expression on various genes. This is prompted by different environmental factors.

Answer 2

Answer;

Operators

Explanation;

• Operator is the regulatory switch which is a segment of DNA, usually positioned within the promoter.
• An Operon is the entire stretch of DNA that includes the operator, the promoter, and the genes that they control.  it is a set of genes transcribed under the control of an operator gene. An operon is a functional unit of transcription and genetic regulation.
• The promoter is the binding site for RNA polymerase, the enzyme that performs transcription. The operator is a regulatory site bound by a repressor protein.