Which of the following is NOT a function of the spleen?

The function that is not associated with the spleen is the production of insulin. The spleen primarily plays roles in the immune system and blood filtration rather than hormone production. It acts as a blood reservoir, storing red blood cells and platelets, and releases them as needed, particularly in response to hemorrhage. It filters blood, removing old and damaged red blood cells as well as pathogens, ultimately playing a critical role in maintaining blood health. Additionally, during fetal development, the spleen is involved in hemopoiesis, which is the process of producing blood cells. However, insulin production is a function of the pancreas, which regulates blood sugar levels, not the spleen. Understanding these distinct roles is crucial for recognizing the biological functions of different organs within the body.