1.4.4 Explain what is meant by passive transport (diffusion, facilitated diffusion), active transport (including the role of ATP), endocytosis and exocytosis and describe the involvement of carrier and channel proteins in membrane transport.

passive transport doesn't require ATP (because it is down a concentration gradient- that is, from high conc. to low conc.).

active transport requires ATP (because it is up a concentration gradient- that is, from low conc. to high conc.).

diffusion is the net, passive, movement of small and/or non-polar lipid-soluble molecules, (e.g. O2 and CO2), directly through the phospholipid bilayer down a concentration gradient.

facilitated diffusion is the net, passive, movement of polar molecules, ions and water-soluble groups through channel proteins down a concentration gradient.

active transport is the movement of all molecules through carrier proteins up a concentration gradient using energy from the breakdown of ATP. 

exocytosis (out of cell) and endocytosis (into cell)- aka bulk transport, which is active:

endocytosis is when large particles of all kinds are transported into the cell using vesicles made from cell surface membrane. 

exocytosis is when vesicles inside the cell fuse with the cell's surface membrane. this transports the vesicles' contents out of the cell.