Genes whose expression is turned off in response to a substance in the environment are known as
A) inducible genes.
B) repressible genes.
C) constitutive genes.
D) inducible genes and repressible genes.
E) All of these are correct.

Question

Quizplus · Accepted Answer

Repressible genes are those that are normally turned on but can be turned off in response to a substance in the environment. Inducible genes are those that are normally turned off but can be turned on in response to a substance in the environment. Constitutive genes are those that are always turned on and are essential for basic cellular functions. Hence, only option B is correct.

Genes Whose Expression Is Turned Off in Response to a Substance