What is one of the main functions of the spleen?

The spleen plays several vital roles in the body, one of which is the storage of red blood cells and platelets. It acts as a reservoir, helping to maintain an adequate supply of these blood components, which are essential for carrying oxygen and facilitating blood clotting. When the body is under stress, such as during physical activity or in certain medical conditions, the spleen can release these stored cells into circulation to meet increased demands.

In addition to its storage function, the spleen also plays a critical role in filtering blood, removing old or damaged red blood cells, and helping mount an immune response to pathogens. This unique combination of functions positions the spleen as an essential organ for both the circulatory and immune systems. Other choices, such as bile production or nutrient absorption, are functions associated with the liver and digestive system, respectively, and are not part of the spleen's role.