Class XI Practical: Physiology - Effect of Heat and Alcohol on Permeability of Beet Root Cell Membranes

Objective

To investigate how temperature (heat) and organic solvents (alcohol) affect the permeability of cell membranes using beet root cells.

Guidelines

1. Sample Preparation: Cut uniform pieces of beet root.
2. Experimental Setup:
   • Heat: Place beet root pieces in water baths at different temperatures (e.g., room temperature, 40°C, 60°C, 80°C, boiling).
   • Alcohol: Place beet root pieces in different concentrations of alcohol solutions (e.g., 0%, 25%, 50%, 75%, 100%).
3. Observation: Observe the intensity of red pigment (betacyanin) leakage into the surrounding solution over a set period. Compare the color intensity qualitatively or quantitatively (e.g., using a colorimeter if available).
4. Analysis: Relate the observed leakage to the denaturation of membrane proteins and disruption of the lipid bilayer by heat and alcohol.

Expected Outcome

Demonstration that extreme temperatures and alcohol disrupt cell membrane integrity, leading to increased permeability and leakage of cellular contents.