Lactase persistence, the ability to digest lactose into adul…

Lactase persistence, the ability to digest lactose into adulthood, is a trait prevalent in some human populations but not others. Which of the following best explains the evolutionary advantage that led to the spread of lactase persistence in certain populations?

The enzyme hexokinase catalyzes the first step of glycolysis…

The enzyme hexokinase catalyzes the first step of glycolysis by adding a phosphate group to glucose. If N-Acetyl-d-glucosamine (NAG) is introduced into the cell, it occupies the active site of hexokinase, thereby preventing glucose from binding, and thus stopping glycolysis. NAG is therefore an example of what?

In human saliva, the enzyme amylase breaks down the starch i…

In human saliva, the enzyme amylase breaks down the starch in foods such as potatoes, rice, and pasta into smaller sugar subunits including its monomer glucose. This process begins in the mouth. If amylase were not present in saliva, the breakdown of starch would still occur, but at a much slower rate. What is the role of salivary amylase in this reaction?