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## Requirements - Fresh clean beet root - Knife - Cork borer - Test tube - Spirit lamp - Ice - Test tube stand - Pepette - Beaker - Distilled water - Methanol - Formaldehyde - Acetone ## Theory The membrane is thin, living, elastic partition that separates protoplast or its components from the su...

## Requirements - Fresh clean beet root - Knife - Cork borer - Test tube - Spirit lamp - Ice - Test tube stand - Pepette - Beaker - Distilled water - Methanol - Formaldehyde - Acetone ## Theory The membrane is thin, living, elastic partition that separates protoplast or its components from the surroundings. All living eukaryotic plant cells possess a membrane outside the cytoplasm known as the plasma membrane or cell membrane, and around the vacuole, it is called the tonoplast. Membranes exhibit selectively permeability or differentially permeability. Membrane permeability is affected by factors like temperature, injury, toxic substances, and leaching. ## Procedure 1. Take a fresh beet root and wash well in tap water. 2. Take out cylindrical pieces of beet root with the help of a cork borer. 3. Cut these cylindrical pieces into equal size of about 5mm thickness with a knife. 4. Wash them thoroughly to remove any trace of anthocyanin (purple pigments). 5. Take 6 test tubes and mark them A, B, C, D, E, and F. 6. Put 10 ml each of distilled water, ice cold water, boiled water, alcohol (methanol), formalin (formaldehyde) and acetone into test tubes A to F respectively. 7. Put two or three slices of beet root into each test tube. 8. Place test tube B (containing ice cold water) in a middle size beaker containing ice water. 9. Place test tube C (containing boiled water) into a beaker containing boiled water to maintain temperature. 10. Test tube A contains slices of beet root kept in distilled water and serves as the control. 11. Put all the test tubes (A, D, E and F) into a test tube stand carefully. 12. After 15 minutes, take out the test tubes and shake them well. 13. Note the intensity of the colour due to the leakage of anthocyanin pigments from slices of beet root. 14. Record the observations in the observation table. ## Observation Table and Results | S.No. | Test tube No. | Liquid taken in the test tube | Change in the colour of the liquid | Degree of leaching | |---|---|---|---|---| | 1. | A | Distilled water (control) | No change | No leaching | | 2. | B | Ice cold water | No change | No leaching | | 3. | C | Boiled water | Purple | Leaching | | 4. | D | Alcohol (methanol) | Dark purple | Maximum Leaching | | 5. | E | Formaline (formaldehyde) | Dark purple | Maximum Leaching | | 6. | F | Acetone | Purple | Leaching | ## Conclusion - The beet root slices placed in distilled water and ice cold water do not show leaching indicating that the membrane permeability is not altered at room temperature (37°C) and low temperature. - In contrast, there is a leakage of pigments from the slices of beet root kept in boiled water indicating an increase in the permeability. - There is maximum leakage of pigments from the slices kept in alcohol and formalin indicating higher permeability of the membrane due to damage of the membrane. - There is also leaching occurring in the test tube containing acetone. ## Precaution 1. The beet root used for the experiment should be fresh and clean. 2. Slices of the beet root should be of equal size. 3. Use equal volumes of liquid in each test tube. 4. Shake the test tubes well to observe the color.