Group MembersGroup Members

Ebone’ Crutcher- Central High

Timberly Wilson- Ridgeway High

Kimberly Jones- Hillcrest High

Brittanye P. Westbrook- Middle College High

Angelo Hutchison- Craigmont High

WHAT IS OSMOSIS & WHAT IS OSMOSIS & DIFFUSION(1)DIFFUSION(1)

Osmosis and Diffusion are processes Osmosis and Diffusion are processes that occur at the cellular level. Both that occur at the cellular level. Both involve the movement of something involve the movement of something from high concentration to low from high concentration to low concentration.concentration.

Diffusion is usually defined as the Diffusion is usually defined as the passive movement of solute particles passive movement of solute particles within a space or through a within a space or through a membrane.membrane.

WHAT IS OSMOSIS & WHAT IS OSMOSIS & DIFFUSION(2)DIFFUSION(2)

Osmosis always refers to the Osmosis always refers to the movement of solvent (water) movement of solvent (water) molecules through a membrane.molecules through a membrane.

The movement of a substance across The movement of a substance across a separating membrane is due to a separating membrane is due to different concentrations of the different concentrations of the substance on each side of the substance on each side of the membrane.membrane.

To find out the rate of osmosis in To find out the rate of osmosis in potato tissue plugs placed in distilled potato tissue plugs placed in distilled water, 10% sodium chloride, or 20% water, 10% sodium chloride, or 20% sodium chloride solutions.sodium chloride solutions.

HypothesisHypothesis

Potato tissues would absorbs water Potato tissues would absorbs water (Turgidity) when placed in a (Turgidity) when placed in a hypotonic solution & would shrink hypotonic solution & would shrink (plasmolysis) in a hypertonic (plasmolysis) in a hypertonic solution. solution.

MaterialsPer Group•Potato plugs•Electronic balance•Graduated cylinders•Paper towels•Distilled water•Timer•Sodium Chloride (NaCl)

1.1. Cut the potatoes into 7.5 cm Cut the potatoes into 7.5 cm plugs. Use a 5mm diameter cork plugs. Use a 5mm diameter cork borer to cut three potato borer to cut three potato cylinders for each beaker. Do not cylinders for each beaker. Do not include the skin.include the skin.

2.2. Keep potato cylinders in a Keep potato cylinders in a covered 400 ml beaker.covered 400 ml beaker.

3.3. Fill beaker #1 with 10% sodium Fill beaker #1 with 10% sodium chloride, beaker # 2 with 20% chloride, beaker # 2 with 20% sodium chloride, and third one sodium chloride, and third one with distilled water only.with distilled water only.

4.4. Take the initial weight of each group of Take the initial weight of each group of potato cylinders and record the mass.potato cylinders and record the mass.

5.5. Let the potato cylinders stand in the Let the potato cylinders stand in the solution for 10 minutes.solution for 10 minutes.

6.6. Every ten minutes remove potato Every ten minutes remove potato cylinders, gently blot with paper towels.cylinders, gently blot with paper towels.

7.7. Take the weight of each group of potato Take the weight of each group of potato cylinders and Record the mass.cylinders and Record the mass.

10% 20% Distilled WaterInitial weight 7.00 gm 6.84 gm 6.97 gm10 mins 6.70 gm 6.26 gm 7.17 gm20 mins 6.49 gm 5.88 gm 7.40 gm30 mins 6.37 gm 5.81 gm 7.42 gm40 mins 6.35 gm 5.41 gm 7.55 gm50 mins 6.25 gm 5.34 gm 7.61 gm60 mins 6.00 gm 5.10 gm 7.50 gm

0.00

1.002.00

3.004.00

5.006.00

7.008.00

Weightsin

gm

Initialw eight

10mins

20mins

30mins

40mins

50mins

60mins

Time in minutes

Effect of Solute Concentration on Osmosis in Potato Plugs

10%

20%

Distilled Water

ComparisonComparisonEffect of Solute Concentration on Osmosis in Potato

Plug

4.004.505.005.506.006.507.007.508.00

Time in minutes

We

igh

t in

gm

10%

20%

Distilled Water

ResultsResults

Potato plugs in distilled water Potato plugs in distilled water imbibed maximum water & Became imbibed maximum water & Became very plump & brittlevery plump & brittle

10% sodium chloride decreased the 10% sodium chloride decreased the weight of potato plugs shrinking the weight of potato plugs shrinking the plugsplugs

20% sodium chloride decreased the 20% sodium chloride decreased the weight of potato plugs the maximum weight of potato plugs the maximum amountamount

Conclusion Conclusion

Potato plugs experiments clearly Potato plugs experiments clearly demonstrarted the principle of demonstrarted the principle of osmosisosmosis