Explain why the steroid hormone estradiol (MW 272) readily crosses membranes by simple diffusion but the much smaller H requires transport proteins

Estradiol has a higher partition coefficient than H+ ions

Explanation

Estradiol is a non-polar and hydrophobic molecule that has a higher partition coefficient than H+ ions, it means that the cell membrane is more permeable to this molecule because it can dissolve in and diffuse within the hydrophobic phase of the membrane. The movement of polar charged molecules (even small H+ ions) requires the input of energy to be able to dissolve within the lipid bilayer. In consequence, the movement of H+ ions requires proteins capable of transporting these protons through the membrane.

six grader is what i am ssorry

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.