What role do white blood cells play in the lymphatic system?

White blood cells, or leukocytes, are crucial for the immune response and play a key role in the lymphatic system by protecting the body from environmental pathogens. They are part of the body's defense mechanism, identifying and attacking harmful organisms, such as bacteria, viruses, and other foreign invaders that can cause disease. The lymphatic system serves as a transport system for these cells, allowing them to move throughout the body to areas where they are needed most, especially during infections or inflammation.

In contrast, transporting oxygen is primarily the role of red blood cells, which carry oxygen from the lungs to the body's tissues. Regulating body temperature involves mechanisms such as sweating and blood flow adjustment, primarily managed by the circulatory system and the nervous system. The breakdown of food is an essential function of the digestive system, where nutrients are extracted from food and distributed to the bloodstream, rather than being related to the functions of the lymphatic system.