What is the primary function of the spleen in the human body?

• A. To filter and store blood, and to mount immune responses
• B. To produce red blood cells
• C. To regulate blood pressure
• D. To produce digestive enzymes

Answer: (A)

Verified step by step guidance

1. Understand the anatomical location and structure of the spleen: The spleen is located in the upper left quadrant of the abdomen, just beneath the rib cage. It is part of the lymphatic system and is involved in various functions related to blood and immunity.
2. Identify the primary functions of the spleen: The spleen filters blood, removing old or damaged red blood cells and platelets. It also stores blood components and plays a crucial role in mounting immune responses by producing white blood cells and antibodies.
3. Differentiate between the functions of the spleen and other organs: While the spleen is involved in blood filtration and immune response, it does not produce red blood cells in adults (this is primarily done by the bone marrow) nor does it regulate blood pressure or produce digestive enzymes.
4. Consider the context of the options provided: The spleen's role in filtering and storing blood and mounting immune responses aligns with its known physiological functions, whereas the other options are functions of different organs or systems.
5. Conclude by selecting the option that best describes the spleen's primary function: Based on the understanding of the spleen's role in the body, the correct answer is that its primary function is to filter and store blood, and to mount immune responses.