If an abnormal repressor protein could still bind allolactose but the binding of allolactose did not alter the conformation of the repressor protein, how would the expression of the lac operon be affected?

When iron is scarce, some bacteria can stop synthesis of all enzymes that require iron (Fe3+), such as superoxide dismutase (SOD). Which of the following accurately describes a mechanism for this regulation? Mark all that apply. A. Regulation occurs by an inducible operon B. When absent, the lack of iron causes the repressor to deactivate and block the promoter region for these genes C. Regulation occurs by a repressible operon D. When present, iron binds and activates the repressor protein

Regarding the tryptophan operon in bacteria, in the presence of tryptophan, tryptophan binds to the Group of answer choices Operon Operator Repressor Promoter RNA polymerase

You identify a mutant that affects lac operon expression. You decide to investigate this mutant further by adding a construct into the mutant's cells that contains a wild type version of the full lac operon as well as lacl. When haploid, the lac operon is uninducible. When the wild type construct is added to make a merodiploid, the lac operon is still uninducible. Based on the mutant phenotypes we learned about in class, indicate which of the following might be mutated in the mutant (if there is more than one possibility, then list them all). O The lac repressor tetramerization/dimerization domain is mutated. The lac repressor ligand-binding domain is mutated. The operator is mutated. The lac repressor DNA-binding domain is mutated. O The lac repressor is deleted in the mutant.