Final answer:
Antigens from connective tissues are carried to lymph nodes by lymphatics, where they are processed and presented to lymphocytes by APCs, triggering an immune response.
Step-by-step explanation:
Antigens derived from infections originating in connective tissues are carried by the lymphatics to the lymph nodes. These bean-shaped structures act as filters, trapping antigens and pathogens as lymph fluid passes through. Inside the lymph nodes, antigen-presenting cells (APCs) such as dendritic cells and macrophages process and present these antigens to nearby lymphocytes, initiating an immune response. Therefore, the lymph nodes play a critical role in the body's defense system by monitoring for foreign invaders and activating appropriate immune responses.