Ch. 5-2.1
Diffusion

from area of high concentration to area of low concentration
redistribution of molecules
Molecular Theory of Motion
	all matter is made of molecules
	molecules are constantly moving
		random motion
Equilibrium
	even concentration
	diffusion stops
	random motion goes on
		maintains at equilibrium
Concentration Gradient
	"concentration difference"
	moves down the concentration gradient
		high to low
Diffusion Pressure
	the force exerted by molecules when they move
	0 at equilibrium point
Factors that affect the rate of diffusion
	mechanical force
		increase in mf = increase in diff.
		i.e. stirring sweet tea
	molecular concentration
		increase concentration = increase diff.
		i.e. adding more sugar than necessary
	temperature
		increase in temperature = increase in diff.
		i.e. cold tea vs. hot tea
	pressure
		increase pressure = increase in diff.
		i.e. plane door opening
Facilitated Diffusion
	diffusion through integral proteins
		carrier/transport proteins
	most molecules cannot cross by simple diffusion
		i.e. glucose b/c it is so huge







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