Which cells are primarily active in the body's immune response to detect and destroy pathogens?

White blood cells play a crucial role in the body's immune response, as they are specifically designed to detect and respond to pathogens such as bacteria, viruses, and other foreign invaders. They include various types of cells, such as lymphocytes (including T cells and B cells), macrophages, and neutrophils, each with specialized functions.

Lymphocytes are pivotal in recognizing specific antigens on pathogens and initiating the adaptive immune response. T cells can directly kill infected cells or help coordinate the immune response, while B cells produce antibodies that neutralize pathogens. Macrophages and neutrophils help in the initial response by engulfing and digesting pathogens through a process called phagocytosis.

The immune system's effectiveness relies on the activity and coordination of these white blood cells, enabling the body to identify and eliminate threats to maintain health. Other cell types, such as red blood cells, platelets, and endothelial cells, have different primary functions within the body, such as oxygen transport, blood clotting, and forming blood vessel linings, respectively, which do not directly participate in immune responses.