What is the main function of the spleen?

The main function of the spleen is to filter blood and produce lymphocytes, which are vital components of the immune system. The spleen plays an essential role in the body's defense against pathogens by identifying and destroying old or damaged red blood cells and filtering out harmful microorganisms and debris from the bloodstream.

Additionally, the spleen serves as a reservoir for lymphocytes, a type of white blood cell that is crucial for adaptive immunity. These lymphocytes respond to specific antigens, allowing for a targeted immune response.

Production of bile is associated with the liver, not the spleen. Storing glycogen is primarily a function of the liver and muscle tissues. Regulating blood sugar is also mainly controlled by the liver and pancreas rather than the spleen. Thus, the spleen’s role in filtering blood and producing lymphocytes uniquely identifies its critical function in maintaining the body’s immune health.