Some genes are expressed at constant levels (constitutive) whereas others are expressed at different levels in response to stimuli (differential). What kind of expression would you expect a gene to have if it were involved in the biosynthesis of actin, a component of the cytoskeleton?
A) It could be either constitutive or differential depending on the organism involved.
B) Differential, as actin is required in all cells at a constant, basal level.
C) Differential, as the cytoskeleton is only required in some cells at some developmental stages.
D) Constitutive, as actin filaments are required in all eukaryotic cells in many important processes including cellular structure.
E) Constitutive, as actin expression is responsive to external stimulants.

Question

Quizplus · Accepted Answer

Actin is a fundamental component of the cytoskeleton in all eukaryotic cells, playing critical roles in processes such as maintaining cell shape, enabling cell movement, and facilitating cell division. Therefore, its expression is generally constant (constitutive) to meet the continuous demand for these essential cellular functions.

Some Genes Are Expressed at Constant Levels (Constitutive) Whereas Others