AP BIOLOGY-Unit 2 Notes

Passive Transport is the net movement of molecules __________ their concentration gradient.

down

Diffusion is the movement of molecules from __________ concentration to __________ concentration.

high, low

Small nonpolar molecules such as __________, __________, and __________ pass freely across a cell membrane.

Nitrogen, oxygen, carbon dioxide

Very small polar molecules like __________ can diffuse across a cell membrane.

water

Facilitated Diffusion involves the movement of molecules from high concentration to low concentration through __________.

transport proteins

Charged ions, including __________ and __________, require channel proteins to cross the membrane.

Na+, K+

Osmosis is the diffusion of __________ across a selectively permeable membrane.

water

Large quantities of water move via __________, which are proteins found in cell membranes.

AQUAPORIN

Active transport moves molecules against their __________ gradient.

concentration

Protein pumps are carrier proteins used in __________.

active transport

Active transport requires __________ input of energy such as ATP.

direct

Endocytosis is when a cell uses energy to take in __________ and particle matter.

macromolecules

Types of endocytosis include __________, __________, and receptor-mediated endocytosis.

phagocytosis, pinocytosis

Exocytosis involves internal vesicles fusing with the __________ membrane.

plasma

A cell can maintain a high concentration of Na+ in the environment by __________ Na+ ions out.

actively transporting

Cell Compartmentalization allows for various metabolic processes to occur __________.

simultaneously