1. List two kinds of single mutations that can change the function of an operator. 2. A bacterial mutation renders a cell incapable of fermenting many sugars (e.g., lactose, sorbitol, xylose)...

1. List two kinds of single mutations that can change the function of an operator.

2. A bacterial mutation renders a cell incapable of fermenting many sugars (e.g., lactose, sorbitol, xylose) simultaneously. The operons of genes specifying the respective catabolic enzymes are wild type (unmutated). Offer an explanation for this phenomenon.

3. Shown below is a hypothetical biosynthetic pathway subject to feedback inhibition; letters represent metabolites; numbers represent enzymes. Identify the enzymes that are most likely to be subject to feedback inhibition and their inhibitor(s). Note: The inhibitor may consist of more than one metabolite.