Living Environment Translated Arabic 2014 | Page 32

p. Passive transport- movement of substances through a cell
membrane without the use of energy; includes diffusion and
osmosis
q. Diffusion- a type of passive transport in which molecules more
from an area of HIGH concentration to an area of LOW
concentration
r. Equilibrium- balance; when molecules of one substance are
spread evenly throughout another substance
s. Concentration gradient- the difference in the concentration ( #
of molecules) of a substance from one location to another
t. Osmosis-a type of passive transport that occurs when water
diffuses through a cell membrane
u. Active transport- the movement of molecules through a
membrane from an area of LOW concentration to an area of
high concentration WITH the use of energy
v. Endocytosis- moving materials into the cell by inward folding
of the cell membrane
w. Exocytosis- moving materials collected in a vacuole out of the
cell through the cell membrane