A Cell In Its Environment

cell membrane

A cell structure that controls which substances can enter or leave the cell.

Exocytosis

a process by which the contents of a cell vacuole are released by the cell membrane.

selectively permeable

a property of cell membranes that allows some substances to pass through, while others cannot

active transport

the movement of materials through a cell membrane using energy

passive transport

the movement of substances across a cell membrane without the use of energy by the cell

Osmosis

diffusion of water across a selectively permeable membrane

Endocytosis

process by which a cell takes material into the cell by engulfing it and turning it into a vacuole.

Diffusion

the process by which molecules move from an area of higher concentration to an area of lower concentration