Give all possible genotypes of a lac operon that produces b-galactosidase and pe
ID: 87269 • Letter: G
Question
Give all possible genotypes of a lac operon that produces b-galactosidase and permease under the following conditions. Do not give partial diploid genotypes(i.e., merozygotes).
Lactose absent.
b-galactosidase permease Genotype
- -
- -
- -
+ +
- -
+ -
- +
lactose present
b-gal. permease Genotype
+ +
- +
+ -
+ +
- -
+ -
- +
Explanation / Answer
lactose absent-
1) lac I gene non-functional.
2) repressor protein is not capable of binding to operator.
3) operator sequence mutation so that it will not allow repressor protein to bind.
lactose present-
1) lac I gene non-functional.
2) repressor protein is not capable of binding to operator.
3) operator sequence mutation so that it will not allow repressor protein to bind.
4) lactose will bind to the repressor protein and inactivates it. so lac operon is functional.