Answer:
It means that the cell membrane allows certain substances to pass through and not others. As the cell membrane consists of a phospholipid bilayer with a hydrophobic core, only small uncharged hydrophobic molecules can pass through the cell membrane e.g. glucocorticoid and other larger charged particles require transporters or channel proteins to pass through the cell membrane, e.g. glucose.
Some ways to describe why the beaks are different from the birds that will only eat nectar and the birds that eat fruit are; the nectar eating birds have longer and thinner beaks. The beaks of the fruit and seed eating birds have have shorter and thicker beaks.
I believe its A i hope that helps
Answer:
a
Explanation:
its talks about the difference