MICROANATOMY

Detailed explanation-1: -Lymph nodes: Lymph nodes are bean-shaped glands that monitor and cleanse the lymph as it filters through them. The nodes filter out the damaged cells and cancer cells. These lymph nodes also store lymphocytes and other immune system cells that attack and destroy bacteria and other harmful substances in the fluid.

Detailed explanation-2: -Lymph collects some waste products, bacteria and damaged cells from inside the body’s tissues so that they can be removed from the body or destroyed. Lymph drains into lymph vessels that carry it to lymph nodes. Lymph nodes clean the lymph and add more lymphocytes to it.

Detailed explanation-3: -Antigens and dendritic cells (DCs) reach the draining lymph node through afferent lymphatic vessels; they must then enter the lymph node and migrate deep into it to activate T cells. Lymph nodes are enclosed in a collagen-rich capsule, which is underlined with lymphatic endothelial cells forming the subcapsular sinus.

Detailed explanation-4: -FQ: What happens to foreign substances in lymph that enter a lymph node? Foreign substances in lymph that enter a lymph node may be phagocytized by macrophages or attacked by lymphocytes that mount immune responses.

Detailed explanation-5: -Lymph nodes function to remove debris and pathogens from the lymph, and are thus sometimes referred to as the “filters of the lymph” (see Figure 11.6). Any bacteria that infect the interstitial fluid are taken up by the lymphatic capillaries and transported to a regional lymph node.