Which solid organ is responsible for blood filtration and immune response?

The spleen is responsible for blood filtration and plays a significant role in the immune response. It acts as a filter for the blood, helping to remove old or damaged red blood cells and pathogens. The spleen contains immune cells, such as lymphocytes and macrophages, which respond to foreign invaders like bacteria and viruses, thereby contributing to the body's defense system.

Additionally, the spleen helps to maintain the balance of blood cells and can produce antibodies to fight infection. Its dual role in filtering blood and activating immune responses makes it crucial for both hematological health and immune function. Understanding the specific functions of the spleen in relation to blood and immune responses highlights its importance as a solid organ in the body.