Q.State the functions of Spleen.

The spleen filters blood, destroys old RBCs, stores blood and iron, produces lymphocytes/antibodies for immunity, and forms blood cells in the foetus.

The spleen is the largest secondary lymphoid organ, situated on the left side of the abdomen behind the stomach. It is richly supplied with blood and contains two types of tissue — red pulp (blood filtering) and white pulp (immune/lymphoid tissue).

Functions of the spleen:

1. Filtration of blood: it removes old, damaged and worn-out red blood cells and platelets from circulation. Because it is the main site where aged RBCs are destroyed, it is called the 'graveyard of RBCs'.
2. Immune function: the white pulp is packed with lymphocytes and macrophages. It produces lymphocytes and antibodies, and traps and destroys blood-borne bacteria and other antigens — an important part of the body's immune response.
3. Blood reservoir: the spleen stores a quantity of blood (and platelets) and releases it into circulation during emergencies such as haemorrhage or heavy exertion. …