NEET BIOLOGY

Detailed explanation-1: -Answer: Osmoregulation. Paramecium and amoeba are freshwater organisms. Because their cytoplasm contains more solutes than their environment, they absorb water through osmosis. Excess water is gathered in a contractile vacuole, which swells before expelling it through a hole in the cell membrane.

Detailed explanation-2: -Osmoregulation in unicellular freshwater organisms like amoebas and paramecia involves an organelle called the contractile vacuole, which collects excess water as it accumulates in the cell and pumps it out.

Detailed explanation-3: -The contractile vacuole acts as part of a protective mechanism that prevents the cell from absorbing too much water and possibly lysing (rupturing) through excessive internal pressure. The contractile vacuole, as its name suggests, expels water out of the cell by contracting.

Detailed explanation-4: -The point of the contractile vacuole is to pump water out of the cell through a process called osmoregulation, the regulation of osmotic pressure. It maintains the shape and internal pressure of the cell.

Detailed explanation-5: -Answer and Explanation: In paramecia, metabolic waste and excess water waste are removed in special sites called anal pore for metabolic waste and contractile vacuole for waste water. The anal pore is located in the vicinity of the oral groove and gullet and for good reason.