IMMUNOLOGY

Detailed explanation-1: -The spleen acts as a filter. It weeds out old and damaged cells and helps control the amount of blood and blood cells that circulate in the body. The spleen also helps get rid of germs. It contains white blood cells called lymphocytes and macrophages.

Detailed explanation-2: -Lymphocytes develop in the thymus and bone marrow (yellow), which are therefore called central (or primary) lymphoid organs.

Detailed explanation-3: -The lymph nodes filter out harmful substances and waste products. They also contain immune cells called lymphocytes that destroy cancer cells and bacteria. The filtered fluid is then returned to the blood circulation. If you have an infection or cancer, a lymph node may become swollen.

Detailed explanation-4: -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.

Detailed explanation-5: -The medullary sinus drains the lymph into the efferent lymphatic vessels. The primary function of lymph nodes is filtering interstitial fluid collected from soft tissues and eventually returning it to the vascular system.

Detailed explanation-6: -Lymph nodes contain lots of white blood cells called lymphocytes. If you have an infection, the lymphocytes multiply inside your lymph nodes. They help fight the infection and make chemicals that activate other parts of your immune system. This is why your lymph nodes swell up when you have an infection.