Capillary embryonic development new capillaries are formed through vasculogenesis, the process of blood vessel formation that occurs through a "de novo" production of endothelial cells which then form vascular tubes. The term angiogenesis denotes the formation of new capillaries from pre-existing blood vessels and already present endothelium which divides. Blood flows from the heart through arteries, which branch and narrow into arterioles, and then branch further into capillaries where nutrients and wastes are exchanged. The capillaries then join and widen to become venules, which in turn widen and converge to become veins, which then return blood back to the heart through
Face transplant the sinuses around the nose, the upper jaw, and even some teeth from a brain-dead donor. As doctors recovered the donor's facial tissue, they paid special attention to maintaining arteries, veins, and nerves, as well as soft tissue and bony structures. The surgeons then connected facial graft vessels to the patient's blood vessels in order to restore blood circulation in the reconstructed face before connecting arteries, veins and nerves in the 22-hour procedure. She had been disfigured to the point where she could not eat or breathe on her own as a result of a traumatic injury several years ago,