What is the role of lymphocytes in the body?

Lymphocytes are a type of white blood cell that play a crucial role in the immune system, specifically in fighting infections. They are key components of the adaptive immune response, which allows the body to recognize and remember pathogens such as viruses and bacteria. When the body encounters an infection, lymphocytes identify and target these invaders for destruction.

There are several subsets of lymphocytes, including T cells and B cells. T cells help to directly kill infected cells or assist other immune cells, while B cells are responsible for producing antibodies that bind to pathogens and neutralize them. This targeted approach allows the body to eliminate pathogens more effectively and provides long-term immunity through memory cells.

In contrast, the other options refer to different body functions that do not involve lymphocytes. The transport of respiratory gases is primarily done by red blood cells, while blood clotting involves platelets and various clotting factors. Nutrient transport is primarily the role of the circulatory system and does not involve lymphocytes. Thus, the primary and distinctive role of lymphocytes is their participation in the immune response to fight infections.