Which of the following best describes the role of lymph nodes during a bacterial infection?

• A. Lymph nodes produce antibodies that directly kill bacteria in the bloodstream.
• B. Lymph nodes filter lymph and contain immune cells that trap and destroy bacteria.
• C. Lymph nodes act as barriers preventing bacteria from entering the circulatory system.
• D. Lymph nodes secrete digestive enzymes to break down bacterial pathogens.

Answer: (B)

Verified step by step guidance

1. Understand the function of lymph nodes in the immune system: Lymph nodes are small, bean-shaped structures that are part of the lymphatic system.
2. Recognize that lymph nodes filter lymph fluid, which carries bacteria, viruses, and other foreign particles from tissues toward the bloodstream.
3. Know that lymph nodes contain immune cells such as lymphocytes (B cells and T cells) and macrophages, which identify, trap, and destroy pathogens like bacteria.
4. Distinguish that lymph nodes do not produce antibodies directly in the bloodstream but facilitate the activation and proliferation of B cells that produce antibodies.
5. Conclude that the best description of lymph nodes' role during bacterial infection is their function as filters of lymph and sites where immune cells trap and destroy bacteria.