Spleen is found on the left part of the abdomen under the ribcage. The spleen contains lymphocyte and macrophages, which destroys bacteria, foreign matter, dead tissue as well as removing them from blood going through the spleen. Spleen functions as a filter peripheral blood. It acts as the defence in the body against disease.
Characteristic of the spleen is primarily related to blood circulation. For example,
(i) Maturation of the surface of erythrocytes.
(ii) Pitting function where spleen removes nuclei from Red Blood Cells.
(iii) Disposal of ageing red blood cells.
(iv) Culling. Here the spleen removes red blood cells
The main characteristic of the spleen which allows it to function in the defence against foreign particles is that they relate primarily to the circulation of the erythrocytes.