Spleen
The spleen is the largest lymphatic lorgan enclosed in the bloodstream. It is site of extensive lymphocytes formation and blood cell storage. The spleen is about 4x7x11 cm large and lies hidden under the ribs in the left upper abdomen.
The spleen recognizes outdated blood cells, filters them out of the blood and breaks them down. The spleen stores up to 30% of the white blood cells in the body.
In addition, platelets are stored in the spleen. These are secreted by the spleen when there is an increased need, such as bleeding. The platelets play a crucial role in blood clotting. The spleen can also recognize and break down small blood clots.