68W Limited Primary Care (LPC) Practice Exam

The main function of the immune system is to defend the body against infections and foreign substances. This system comprises a complex network of cells, tissues, and organs that work together to identify and eliminate pathogens such as bacteria, viruses, fungi, and parasites, as well as any other substances that may be harmful to the body, including allergens and toxins.

The immune response involves several key components, including white blood cells (like lymphocytes and macrophages), antibodies, and various signaling molecules. These elements coordinate to detect invaders, mobilize defenses, and remember previous encounters with pathogens to mount a faster and more effective response in future infections. By providing this protective mechanism, the immune system plays a crucial role in maintaining overall health and preventing disease.

Regarding the other options, assisting in digestion relates to the digestive system, producing hormones is primarily a function of the endocrine system, and regulating body temperature is the role of the thermoregulatory system. Each of these systems has distinct functions that do not overlap with the primary role of the immune system.