For an enzyme to effectively change its activity in response to a change in substrate concentration, it is most favorable for:

a) km to be less than cellular substrate concentrations.
b) km to be equal to cellular substrate concentrations.
c) km to be greater than cellular substrate concentrations.
d) vmax to be at the diffusion limit.
e) the substrate to also be an allosteric effector.

The substrate to also be an allosteric effector.

Explanation:

Inositol hexaphosphate (IHP) is an example of an allosteric effector, which are known substances that bind to the site of an enzyme, that are allosteric in nature, thereby leading to a corresponding increase or decrease in the activities of the enzyme.  These effectors can cause a change in the configuration of the enzymes by binding to a non-active site.

A positive allosteric effect do cause an increase in the activities of the enzyme while the negative allosteric effect causes the decrease in the activities of the enzymes.

the scientific method.

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.