The lac operon is responsible for the production of a regulatory molecule polypeptides that permit e. coli to use a specific sugar as a carbon source for metabolic energy. the lac operon acts as a genetic switch to begin sugar break down, but only if
(1) lactose is present in the cell; and
(2) all glucose has been depleted.

(1) lactose is present in the cell; and

(2) all glucose has been depleted.

Explanation:

Operon  are Clusters of gene that undergo coordinated transcription, and share regulatory regions. Lactose Operon  is the operon responsible for the production of three polypeptides that permit E. coli to utilize the sugar lactose as a carbon source for growth and metabolic energy

Functional Sequences of the Lac Operon  are:

osteogenesis imperfecta (oi) refers to a congenital ailment of bones. in the condition, the bones become brittle or fragile. this ailment is a general result of the defect or mutations in the genes (colia1 or colia2). this mutation results in imperfect collagen formation either in quantity or quality wise.  

there are eight kinds of oi defects, and each kind varies with certain distinctions in symptoms. the usual symptoms include frequent bone fractures, loss of hearing in infants, protruding eyes, discoloration of the white in the eyes, respiratory issues, loosening of the joints, short stature, and other symptoms.