What is the primary function of white blood cells?

The primary function of white blood cells (WBCs), also known as leukocytes, is to defend against infection. These cells are a key component of the immune system and play a crucial role in identifying and combatting pathogens such as bacteria, viruses, and other foreign invaders. When an infection occurs, white blood cells are activated and mobilized to the site of infection, where they can either directly destroy pathogens or produce antibodies that help mark these invaders for destruction by other immune cells.

In addition to their role in fighting infections, white blood cells are also involved in allergy responses and immune surveillance, which helps to identify and eliminate cancerous cells. The various types of WBCs, including lymphocytes, neutrophils, monocytes, eosinophils, and basophils, each have specific roles in the immune response, but their overarching purpose revolves around protecting the body from disease and maintaining health.