What is the function of lymphocytes in the body?

Lymphocytes are a type of white blood cell that plays a crucial role in the immune system. Their primary function is to fight infection by identifying and attacking pathogens such as viruses, bacteria, and other foreign invaders. Lymphocytes are essential for both the innate and adaptive immune responses. There are different types of lymphocytes, including B cells and T cells, each with a specific role in recognizing and destroying harmful substances.

The other choices refer to functions that are not performed by lymphocytes. For example, the transportation of oxygen is mainly performed by red blood cells, and maintaining body temperature involves various physiological processes and mechanisms that regulate heat production and loss. Regulating blood pressure involves the cardiovascular system and is influenced by factors such as blood vessel diameter and heart rate, rather than being a function of lymphocytes. Thus, the understanding of lymphocytes as infection fighters is key in comprehending their importance in the body's overall immune response.