Final answer:
The statement is false; the spleen primarily filters blood, removing old red blood cells and pathogens, whereas lymph nodes filter lymph fluid, not blood.
Step-by-step explanation:
False, the spleen and lymph nodes have similar but not identical functions in the body. While both are involved in the immune response, their primary functions are somewhat different. The spleen filters blood, removing worn-out red blood cells and pathogens. It has two distinct areas: red pulp, which is responsible for filtering and storing blood, and white pulp, which is rich in lymphocytes that remove antigen-coated bacteria from the circulating blood.
In contrast, lymph nodes filter lymphatic fluid, not blood. They contain immune cells that can detect and respond to pathogens present within the lymph. Therefore, the spleen is primarily involved with blood, while lymph nodes handle the filtration and immune response concerning the lymph fluid.