Ch. 5-2.2
Osmosis

diffusion of water
goes through semi-permeable membrane
direction
	from high to low
	down the concentration gradient
Reaction of plant and animal cells in solutions of different concentrations
	Isotonic
		equal inside & outside
		
			Inside
				solute-7%
				H2O-93%
			Outside
				solute-7%
				H2O-93%
		same amount goes out as in
	Hypotonic
		hypo-under / less than
		less inside than outside
		
			Inside
				solute-7%
				H2O-93%
			Outside
				solute-2%
				H2O-98%
		water comes in
		causes swelling, possibly bursting
			cytolysis
Hypertonic
	hyper-more than
		Hyperactive children
	less outside than inside
		
			Inside
				solute-7%
				H2O-93%
			Outside
				solute-10%
				H2O-90%
		water goes out
		causes cells to shrivel up
			plants
				plasmolysis
			animals
				crenate
Osmotic Pressure
	diffusion pressure of water
Plant cells analogy
	cell wall : cell membrane :: cardboard box : balloon
Turgor pressure
	force a plant cell exerts on its cell wall
	wilting -very little turgor pressure
		limp/soft
	turgid - a lot of turgor pressure
		crisp/stiff/firm
Animals adapting:
	Hypotonic solutions
		i.e. distilled water
			100% H2O
			0% solute
		avoid cytolysis
		contractile vacuole
			uses energy(ATP)
			Active transport
			i.e. paramecium
	Hypertonic Solutions
		i.e. salt water
		avoid plasmolysis/crenate
			sharks put more oil in cell







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