?

Genetics and Genomics

Free Version

Upgrade subject to access all content

Moderate

Prokaryotic Gene Expression Control

GENES-CJH4I3

Gene regulation is essential for prokaryotic cells, as it increases the adaptability of an organism by allowing the cell to express proteins on an as-needed basis.

Choose the correct statement below about gene regulation.

A

Up-regulation is triggered by a signal which results in decreased expression of one or more genes, leading to lowered production of the protein(s) encoded by those genes.

B

Down-regulation occurs when a cell is overstimulated by a specific molecule for a prolonged period of time, and the expression of the receptor protein is increased in order to protect the cell.

C

A repressible system is turned on except in the presence of some molecule (called a repressor); this molecule suppresses gene expression.

D

An inducible system is turned on unless there is the presence of some molecule (called an inducer) that allows for gene suppression.