Movements across membranes

Question	Answer
Diffusion	the movement of particles from a higher concentration to a lower concentration until they are spread out evenly
Osmosis	Diffusion of water the passage of water molecules from a dilute solution into a more concentrated solution through a partially permeable membrane
Active transport	the uptake of particles by cells against a concentration gradient. Needs energy.
Factors that affect rate of movement of subtances into and out of cells	Surface Area to Volume ratio Temperature Concentration gradient
Surface Area to Volume ratio	with a large SA:V ratio, more food and oxygen can be absorbed (through the surface) in order for the cell to respire therefore, the rate of movement of substances into and out of cells increases
Temperature	When temperature increases, collisions between particles occur more frequently as they gain more kinetic energy therefore, the rate of movement of substances into and out of cells increases
Concentration gradient	Particles move faster down a steep concentration gradient (high to low)

Resource summary

	Created by karina_p almost 9 years ago