Suppose that the amino acids that make up an enzyme’s active site are changed. how might this change affect the enzyme?

People who exercise for an hour may have lower cholesterol levels. is that a statement? a law? or a hypothesis?

Y’all i need answers plss people are saying me and my brother look alike although we’re two different ages. one year apart i’m a girl, btw i’m thinking we could be fraternal twins idk my parents and my friends think we look alike

Hummingbirds drink nectar from flowers, while robins eat plant seeds. what does this reduce?