60 ❯ STEP 4. Review the Knowledge You Need to Score High
Osmosis:passive movement of water from the side of low solute concentration to the side of
high solute concentration (hypotonic to hypertonic).
Facilitated diffusion:assisted transport of particles across membrane (no energy input needed).
Active transport:movement of substances against concentration gradient (low to high con-
centrations; requires energy input).
Endocytosis:phagocytosis of particles into a cell through the use of vesicles.
Exocytosis:process by which particles are ejected from the cell, similar to movement in a
trash chute.