Which body system is responsible for protecting the body from disease?

The immune system is the body's primary defense mechanism against pathogens, including viruses, bacteria, and other disease-causing organisms. It is composed of various cells, tissues, and organs that work together to identify and destroy foreign invaders. Key components of the immune system include white blood cells, antibodies, and the lymphatic system, all of which play critical roles in detecting and responding to threats to the body’s health.

The immune system not only protects against infections but also helps in the elimination of transformed cells that could potentially lead to cancer. It has a remarkable ability to remember past infections, allowing for a faster and more effective response upon subsequent exposures. This adaptive aspect makes the immune system essential for maintaining overall health and well-being.

In contrast, the other systems mentioned have different primary functions. The circulatory system is responsible for transporting nutrients, gases, and waste products throughout the body. The respiratory system enables gas exchange, primarily the intake of oxygen and the expulsion of carbon dioxide. The digestive system breaks down food, absorbing nutrients and eliminating waste. While all these systems contribute to overall health, it is specifically the immune system that plays a direct role in protecting the body from disease.