Differentiate between excretion ands osmo-regulation? Describe how excretion takes place in amoeba.

Excretion is a process in which any living organism removes their metabolic waste from the body.

Osmoregulation is the physiological process that an organism uses to maintain water balance.

Amoeba is a unicellular organism found in fresh water. Amoebas eat algae, bacteria, plant cells, and microscopic protozoa and metazoan – some amoebas are parasites. They eat by surrounding tiny particles of food with pseudo pods, forming a bubble-like food vacuole. The food vacuole digests the food.

The waste material carbon dioxide is removed by the process of diffusion though the cell membrane and the nitrogenous waste mainly ammonia is excreted with the help of the contractile vacuole.

Specific excretory organs are absent in unicellular organisms like amoeba. These organisms remove waste products by simple diffusion from the body surface into the surrounding water. Amoebas possess osmo-regulatory (osmotic pressure) organelle called contractile vacuole. This collects water and waste from the body, swells up, reaches the surface and bursts to release its content to outside. The main excretion takes place through body surface by the process of osmosis. Thus, waste products are exceeding in amoeba.