Which system is primarily responsible for fighting infections?

The lymphatic system is primarily responsible for fighting infections due to its crucial role in the immune response. This system consists of a network of lymphatic vessels, lymph nodes, and organs such as the spleen and thymus. It helps maintain fluid balance in the body and is essential for transporting lymph, which contains white blood cells, particularly lymphocytes. These cells play a key role in identifying and combating pathogens like bacteria and viruses.

When an infection occurs, the lymphatic system responds by activating various immune cells that contribute to the body's defense. Lymph nodes act as filters, trapping pathogens and allowing immune cells to proliferate and mount an attack. Additionally, the spleen helps filter the blood and plays a role in removing old or damaged blood cells while generating immune responses.

In contrast to this, the nervous system primarily manages body responses to stimuli, the digestive system processes food and absorbs nutrients, and the endocrine system regulates bodily functions through hormones. While these systems play important roles in overall health, the lymphatic system stands out as the primary defender against infections.