What role do antigens play in the immune response?

Antigens are substances that the immune system recognizes as foreign, and their role is primarily to function as chemical markers for recognition. When pathogens such as bacteria, viruses, or other foreign molecules enter the body, antigens present on their surface are detected by immune cells. This recognition triggers an immune response, allowing the body to identify and respond to threats effectively.

The immune system utilizes various cells, such as B cells and T cells, to recognize these antigens. For instance, B cells can produce specific antibodies that bind to antigens, marking them for destruction or neutralization. This recognition process is crucial for the adaptive immune response, which learns and remembers the specific antigens associated with pathogens, providing long-lasting immunity.

Understanding the function of antigens is fundamental to grasping how the immune system operates to protect the body against infections. It highlights the importance of recognition in initiating appropriate immune responses, while other options might describe related but distinct aspects of immune function or processes.