Answer :
When an amoeba is placed in distilled water, it tends to take in water by the process of osmosis. Osmosis is the movement of water from an area of high water concentration to an area of low water concentration through a selectively permeable membrane.
To regulate the amount of water in its body when placed in distilled water, an amoeba employs a mechanism known as contractile vacuoles. Contractile vacuoles are organelles that collect excess water from the cytoplasm and expel it from the cell to prevent it from bursting due to excessive water uptake.
Here is a step-by-step explanation of how an amoeba regulates the amount of water in its body when placed in distilled water:
1. When the amoeba is placed in distilled water, water diffuses into the cell due to the higher water concentration outside the cell compared to inside.
2. As water enters the cell, the contractile vacuoles fill up with excess water from the cytoplasm.
3. The contractile vacuoles then contract rhythmically to expel the accumulated water out of the cell through a pore in the cell membrane.
4. By continuously expelling excess water, the amoeba maintains its internal water balance and prevents excessive swelling that could potentially harm the cell.
In summary, when placed in distilled water, an amoeba uses contractile vacuoles to regulate the amount of water in its body by actively expelling excess water to maintain osmotic balance and prevent cell damage.
