Red blood cell synthesised by the kidney. Just before and after leaving the bone marrow, the developing cells are known as reticulocytes; these constitute about 1% of circulating red blood cells. The functional lifetime of a red blood cell is about 100–120 days, during which time the red blood cells are continually moved by the blood flow push (in arteries), pull (in veins) and a combination of the two as they squeeze through microvessels such as capillaries. They are also recycled in the bone marrow. The aging red blood cell undergoes changes in its plasma membrane, making it susceptible to selective recognition by
Vasa vasorum Vasa vasorum The vasa vasorum is a network of small blood vessels that supply the walls of large blood vessels, such as elastic arteries (e.g. aorta) and large veins (e.g. venae cavae). The name derives . Studies conducted with 3-dimensional microcomputed tomography (3D Micro-CT) on pig and human arteries from different vascular beds have shown that there are three different types of vasa vasorum: Depending on the type of vasa vasorum, it penetrates the vessel wall starting at the intimal layer (vasa vasorum interna) or the adventitial layer (vasa vasorum externa). Due to higher radial and circumferential pressures within the