Scientists can use mutants to study metabolic pathways. These organisms have a mutation in a gene encoding a metabolic pathway enzyme that results in the inactivation of that enzyme. Saccharomyces cerevisiae (a yeast species) mutants are available that grow on fructose, but not glucose. This growth defect results from a mutation in the gene encoding what enzyme? a. phosphoglycerate kinase
b. enolase
c. pyruvate kinase
d. phostphoglycerate mutase
e. Phosphoglucose isomerase (phosphohexose isomerase or glucose-6-phosphate isomerase)

The correct answer is - e. Phosphoglucose isomerase (phosphohexose isomerase or glucose-6-phosphate isomerase)

Explanation:

Phosphoglucose isomerase (phosphohexose isomerase or glucose-6-phosphate isomerase) is an enzyme that catalyzes the conversion of the glucose-6-phosphate to fructose-6-phosphate or fructose-6-phosphate to glucose-6-phosphate.

In the given question there most likely a mutation that takes place in Phosphoglucose isomerase as it is not able to convert glucose to fructose which is a growth defect.

answer:   option a) glucagon was secreted by his pancreas before he ate the cookies because blood glucose was low. insulin was secreted after he ate the cookies because his blood glucose was high.

explanation:

i think it is d. objects resist changes in their state of motion.