Pertaining to the lymph system or lymph tissue, the "back alley" of blood circulation. Lymph is the alkaline, clear intercellular fluid that drains from the blood capillaries, where the arterial blood separates into thick, gooey venous blood and lymph. It bathes the cells, drains up into the lymph capillaries, through the lymph nodes for cleaning and checking against antibody templates, up through the body, and back to recombine with the venous blood in the upper chest. Blood in the veins is thick, mainly because part of its fluid is missing, travelling through the tissues as lymph. Lymph nodes in the small intestine absorb most of the dietary fats as well-organized chylomicrons. Lymph nodes and tissue in the spleen, thymus, and tonsils also organise lymphocytes and maintain the software memory of previously encountered antigens and their antibody defence response. Blood feeds the lymph, lymph feeds the cells, lymph cleanses the cells and returns to the blood.