Which of the following is a role of lymph nodes in the immune system?

• A. They filter lymph to remove pathogens and debris.
• B. They secrete digestive enzymes into the small intestine.
• C. They produce insulin to regulate blood sugar.
• D. They generate electrical impulses for muscle contraction.

Answer: (A)

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. Their primary role is to filter lymph, a fluid containing white blood cells, to remove pathogens, debris, and abnormal cells.
2. Eliminate incorrect options based on biological knowledge: Lymph nodes do not secrete digestive enzymes into the small intestine, as this is the role of the pancreas and other digestive organs.
3. Eliminate the option related to insulin production: Insulin is produced by the pancreas, not lymph nodes, and is involved in regulating blood sugar levels.
4. Eliminate the option related to generating electrical impulses: Electrical impulses for muscle contraction are generated by neurons, not lymph nodes.
5. Confirm the correct answer: The role of lymph nodes in the immune system is to filter lymph to remove pathogens and debris, supporting the body's defense mechanisms.