# Biology Required Practical: Osmosis

Includes;

- The Method (In Blue)

- Safety Notes (In Pink)

• Created by: Hannah
• Created on: 19-03-19 19:20
• Biology Required Practical: Osmosis
• 1. Use a cork borer to cut five potato cylinders of the same diameter.  Trim the cylinders so that they are all the same length (about 3 cm).
• 2. Accurately measure and record the length and mass of each potato cylinder.
• 3. Measure 10 cm cubed of the 1.0M sugar solution and put into the first boiling tube. Label boiling tube as: 1.0.M sugar.
• 4. Repeat step 3 to produce the additional labelled boiling tubes containing solutions of 0.75M, 0.5M. and 0.25M.
• 5. Measure 10 cm cubed of the distilled water and put into the fifth boiling tube.  Label boiling tube as water.
• 6. Add one potato cylinder to each boiling tube. Make sure you record the length and mass of each potato cylinder in each boiling tube.
• 7. Leave the potato cylinders in the boiling tubes overnight in the test tube rack. Next morning, remove the cylinders from the boiling tubes and carefully blot them dry with the paper towels.
• 8. Re-measure the length and mass of each cylinder. Then calculate the changes in length and mass of each potato cylinder.
• 9. Plot two graphs, each with the concentration of sugar solution on the x-axis. Then, add either change in mass or change in length on the y-axis.
• Care should be taken with the use of cork borers and scalpels when students are cutting their own potato cylinders.
• Care should be taken with the use of an electrical balance in the presence of water.