The walls of cells need to be selective permeable. That means they need to be selective about what they let out and in.

osmosis diffusion concentration

osmosis the fact that something moves through a membrane so there is equal pressure on either side of the membrane. Think of it being like crowded peopl ei n an elevator, as saoon as the doors open the people rush out. Basically it moves from more crowded places to less crowded places.

If the concenrtraion of a solution i shigher inside the cell than outisde then that is called hypertonic. If it’s higher outside the cell than inside then it’s called hypotonic. When water moves from a place of higher concentration to lower concentration it’s called moving across it’s concentration gradient.

Aquaporins in cells?

If something has to move from a low concentration to a high concentraion that’s called active transport. ? High energy transport is moving something in reverse of the concentration gradient ? Most cells ? have something called a sodium – potassium pump.

excocytosis ?

pinocytosis how cells absorb nutrients ?

Vesicular transport is done by vesicles

This works against both the electro chemical gradient and the concentraiton gradient ?

The kidneys are constantly trying to regulate th eblood plasma to make it isotonic ?

When it’s equal inside and out of the cell it’s called isotonic?

There’s two ways to cross the cell membrane: active transport & passive transport. ?

Passive transport is easy for things like oxygen and water to get in and out of the cell.