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
Endometrial arteries body and they enrich the endometrium of the uterus. The joining of endometrial arteries and veins of the endometrium is known as arteriovenous. Endometrial arteries are also involved in the menstrual cycle. When the egg implants onto the endometrium and is not fertilized the endometrial arteries become narrow and the endometrium begins to disintegrate. This is when the endometrium sheds and results in menstruation. Endometrial arteries Arcuate arteries located in the uterus branch out and supply blood to different layers of the uterus. These arteries meet the myometrial-endometrial junction and lead to straight and endometrial arteries. The endometrium receives blood