What are lymph nodes?

What are lymph nodes?

• A. Oval-shaped structures that filter lymph and trap harmful substances
• B. Small sacs storing blood
• C. Glands producing hormones
• D. Pumps lymph through vessels

Answer: (A)

Lymph nodes are small, oval organs in the lymphatic system that filter lymph as it passes through. They house immune cells, including macrophages that engulf debris and pathogens, and B and T lymphocytes that respond to antigens. This filtering traps harmful substances and helps coordinate immune responses, which is why these nodes swell during infections. They aren’t storage sacs for blood, nor are they hormone-secreting glands, and lymph is moved by contractions of lymph vessel walls and surrounding muscles rather than a single pumping organ.

Lymph nodes are small, oval organs in the lymphatic system that filter lymph as it passes through. They house immune cells, including macrophages that engulf debris and pathogens, and B and T lymphocytes that respond to antigens. This filtering traps harmful substances and helps coordinate immune responses, which is why these nodes swell during infections. They aren’t storage sacs for blood, nor are they hormone-secreting glands, and lymph is moved by contractions of lymph vessel walls and surrounding muscles rather than a single pumping organ.