If operator gene is deleted due to mutation, how will E. coli metabolise lactose?

Given that the average duplication time of E. coli is 20 minutes how much time will two E.coli cells take to become 32 cells?

In medium where E. coli was growing lactose was added, which induced the lac operon. But why does lac operon shut down after some time after addition of lactose in the medium?

Name the following Diseases or disorders occurring due to abnormalities in chromosomes and mutations in genes

Diagrammatically represent the experimental steps in cloning and expressing a human gene ( say the gene foe insulin)into a bacterium like E. coli.

E. coli hygromycin resistance gene is used in ________