Incipient Point of Plasmolysis Lab
Investigation of the point of incipient plasmolysis of onion cells (Allium cepa) using NaCl (Sodium Chloride) concentrations of 0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M
Design
Research Question (Aim):
The aim of this lab was to determine the point of incipient plasmolysis of onion (Allium cepa) cells using Sodium Chloride (NaCl) concentrations of 0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M.
Hypothesis:
When the water concentration of a solution outside the cell is lower than the concentration inside the cell, water will move from the inside to the outside of the cell due to osmosis. As we increase the concentration of the NaCl solutions we have used (0.1M to 0.6M), more moles of NaCl are dissolved in the solution. Thus, the solutions increases in solute concentration but decreases in water concentration. We can therefore assume; the higher the concentration of the NaCl solution, the higher the number of plasmolysed cells as water moves outside the cell in order to dilute the NaCl concentration.
Data Collection and Processing
Table 1:
The number of plasmolysed onion cells (out of 30) ±1 for each of the 6 NaCl concentrations (0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M) for three trials
|Concentration (in M) |Trial 1 (Number of Plasmolysed |Trial 2 (Number of Plasmolysed |Trial 3 (Number of Plasmolysed |
| |Cells ±1) |Cells ±1) |Cells ±1) |
|0. 1 |0 out of 30 |0 out of 30 |0 out of 30 |
|0. 2 |2 out of 30 |0 out of 30 |0 out of 30 |
|0. 3 |6 out of 30 |4 out of 30 |3 out of 30 |
|0. 4 |6 out of 30 |12 out
Design
Research Question (Aim):
The aim of this lab was to determine the point of incipient plasmolysis of onion (Allium cepa) cells using Sodium Chloride (NaCl) concentrations of 0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M.
Hypothesis:
When the water concentration of a solution outside the cell is lower than the concentration inside the cell, water will move from the inside to the outside of the cell due to osmosis. As we increase the concentration of the NaCl solutions we have used (0.1M to 0.6M), more moles of NaCl are dissolved in the solution. Thus, the solutions increases in solute concentration but decreases in water concentration. We can therefore assume; the higher the concentration of the NaCl solution, the higher the number of plasmolysed cells as water moves outside the cell in order to dilute the NaCl concentration.
Data Collection and Processing
Table 1:
The number of plasmolysed onion cells (out of 30) ±1 for each of the 6 NaCl concentrations (0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M) for three trials
|Concentration (in M) |Trial 1 (Number of Plasmolysed |Trial 2 (Number of Plasmolysed |Trial 3 (Number of Plasmolysed |
| |Cells ±1) |Cells ±1) |Cells ±1) |
|0. 1 |0 out of 30 |0 out of 30 |0 out of 30 |
|0. 2 |2 out of 30 |0 out of 30 |0 out of 30 |
|0. 3 |6 out of 30 |4 out of 30 |3 out of 30 |
|0. 4 |6 out of 30 |12 out
Cited: Stadelmann, E. J. Methods in Cell Physiology. Ed. David M. Prescott. New York: Academic, 1966. Print.