Lymph nodes contribute to immune defense by producing which cells?

• A. Lymphocytes
• B. Erythrocytes
• C. Platelets
• D. Neurons

Answer: (A)

Lymph nodes are centers where the adaptive immune response is activated and expanded. They bring together lymphocytes with antigens and antigen-presenting cells, allowing B cells and T cells to encounter pathogens, become activated, and proliferate. This clonal expansion increases the number of lymphocytes ready to fight infection, making lymphocytes the cells central to the immune action that lymph nodes support. In contrast, erythrocytes and platelets come from bone marrow and carry oxygen or aid clotting, while neurons are nerve cells, not part of immune defense.