The answer is D.
This is because in all the other examples both males, the squares, and females, the circles, inherit freckles. But I’m example D. only males, the squares, inherit freckles. Hope this helps!!
Integral proteins are embedded in the phospholipid layer, and can sometimes form protein channels that let ions and other small molecules through.
Answer:
they have thin membranes to allow diffusion of substance for short distance
they are numerous to increase the surface area of absorption
hope this helps
3:they are usually microscopic