The following table lists several genotypes associated with the lac operon in E.

Question

The following table lists several genotypes associated with the lac operon in E. coli. For each indicate with a "+" or a ," whether -galactosidase would be expected to be produced at induced levels. (Assume that glucose is not present in the medium.) Correct Part B No Lactose Lactose For the genotype which of the following should be entered into the chart? Iwild-type repressor mutant repressor (unable to bind to the operator) = mutant repressor (insensitive to lactose) 0' = wild-type operator costitutive operator (insensitive to repressor) Submit Incorrect; Try Again; 5 attempts remaining

Explanation / Answer

The genotype has mutant repressor which means that the repressor can not bind to the operator region. Since the operator region is free RNA polymerase enzyme can bind to the promoter region and transcribe the lacZ gene. In the absence of lactose in this case, since the operator region is constitutive, transcription of lacZ gene occurs. In the presence of lactose, transcription of lacZ gene occurs. So, the correct option is option A, + +.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.