What is the function of white blood cells in the immune system?

• A. To transport oxygen in the bloodstream
• B. To provide structural support to tissues
• C. To combat infections and foreign substances
• D. To aid in nutrient absorption

Answer: (C)

White blood cells play a crucial role in the immune system, primarily tasked with defending the body against infections and foreign substances. They are essential components of the immune response, acting to identify, target, and eliminate pathogens such as bacteria, viruses, and other harmful invaders.

These cells are versatile and come in various types, each with specific functions. For example, lymphocytes (which include T cells and B cells) are responsible for recognizing specific antigens and coordinating the immune response, while phagocytes (like macrophages) engulf and digest pathogens. This intricate function of combating infections helps to maintain the body’s health and homeostasis.

The other options represent roles that are not associated with white blood cells. For instance, the transportation of oxygen is predominantly the function of red blood cells, structural support to tissues is mainly provided by connective tissues, and nutrient absorption is a role performed by the cells lining the intestines. Therefore, the unique and pivotal function of white blood cells in combating infections underscores their critical role in the immune system.