Experiment: Turgor in Potato Tissue
Experiment: Turgor in Potato Tissue 1. We labelled three test tubes A, B, C, D and added initials of people in our group. 2. Used a syringe or graduated pipette to put 20 cm3water in tube A and 10 cm3 in tube B. 3. Put 20 cm3 of 17% solution in tube C and 10 cm3 in tube B; put 20 cm3 pure sucrose solutions in tube D. 4. Working on the dissecting board I cut the ends off large potato. I was careful with the knife and cut it onto the dissecting board away from myself. 5. Used a cork borer to obtain 4 cylinder of potato tissue and pushed the potato tube out of the borer using a pencil. 6. Cut all these potato cylinders to same length using a scalpel-cut carefully away from my body. 7. I recorded the initial length of the potato cylinders on my result table. 8. Then I also measured the mass of each potato cylinder by placing in onto measuring scale and recorded the mass in the result table. 9. Afterwards the potato cylinder were placed into each test tube A, B, C, D. Leave it for 24 hours. Tubes | Initial Mass /g | Final Mass/g | Initial Length/mm | Final length/mm | A | 2.9g | | 55mm | | B | 2.9g | | 55mm | | C | 3.0g | | 55mm | | D | 3.0g | | 55mm | | Theory Osmosis is the movement of water across a partially permeable membrane.
Theory and Predictions
A- Pure Water
B- 4.26% glucose
C-8.5% glucose solution
D-34% glucose solution
In tube A the potato mass will increase as the water will move into the potato by osmosis causing it to expand.
In tube B, C the potato will also increase in mass and volume but not as much as in tube A.
In tube D we have a very concentrated solution so water will be drown out of the potato by osmosis causing it to shrink, i.e. decrease in mass and volume.
Conclusion: Tube A= pure water: water moved into the potato cylinder by osmosis . It caused the potato to expand, as a result the mass