AP BIOLOGY

Detailed explanation-1: -thus the correct answer is diffusion.

Detailed explanation-2: -Diffusion is the movement of molecules from an area of high concentration to an area of low concentration. The diffusion of water across a membrane because of a difference in concentration is called osmosis.

Detailed explanation-3: -Passive transport is a way that small molecules or ions move across the cell membrane without input of energy by the cell. The three main kinds of passive transport are diffusion, osmosis, and facilitated diffusion.

Detailed explanation-4: -The diffusion of water molecules through a selectively permeable membrane is known as osmosis.

Detailed explanation-5: -Answer and Explanation: The molecules that would not be able to pass the membrane by simple diffusion are Na+ (sodium cations) and cellulose. Na+ moves across the plasma membrane by facilitated diffusion as they require ion channels to move across.