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Unit 4 Biology

Biology Unit 4 Vocabulary

Active Transport Movement of substances through the cell membrane that REQUIRES ENERGY. Moving things from a LOW concentration to a HIGH concentration.
Passive Transport Movement of substances through a cell membrane DOES NOT require energy (diffusion and osmosis)
Cell Membrane A flexible boundary that controls the movement of substances into and out of the cell
Diffusion Movement of molecules from an area of HIGH concentration to an area of LOW concentration.
Homeostasis Process by which organisms maintain a relatively stable internal environment.
Selective Permeable A property of cell membranes that allows some substances to pass through, while others cannot.
Osmosis Diffusion of WATER molecules through a semi-permeable membrane from HIGH concentration to LOW concentration.
Created by: ladyg747