HUMAN BODY SYSTEMS Skeletal Muscular Circulatory Lymphatic Digestive Excretory Endocrine Reproductive Skin Respiratory

LYMPHATIC SYSTEM The lymphatic system is not really a separate system of the body. It is considered part of the circulatory system since it consists of lymph, a moving fluid that comes from the blood and returns to the blood by way of the lymphatic vessels. Lymph carries some nutrients around the body, especially fat. It also distributes germ-fighting white cells.

Lymph resembles plasma, but is more diluted and contains only about 5% of proteins and 1% of salts and extractives. It is formed from bits of blood and other body liquids, called interstitial fluid or tissue fluid, that collect in the spaces between cells. The lymph picks up any particles that are too big to be absorbed through the capillary membrane. These include cell debris, fat globules, and tiny protein particles. The lymphatic system is a secondary transport system. Lymph has no pump of its own. Its flow depends on pressure from the blood system and the massaging effect of the muscles.

The spleen is closely associated to both the circulatory and the lymphatic systems. It is an abdominal organ which lies between the bottom of the stomach and the diaphragm. It plays a role in the maintenance of blood volume, production of some types of blood cells, and recovery of material from worn out red blood cells. It is also involved in the removal of blood cells and bacteria from the blood.

Lymph nodes, or lymph glands as they are sometimes called, are small oval structures normally the size of small kidney beans. They generally are located in clusters near veins at strategic points along medium-sized lymph vessels at the knee, elbow, armpit, groin, neck, abdomen and chest. Blood is cleaned and filtered in the lymph nodes, and germ fighting cells gather there during illness.