Nearby USPS - Postal Service Locations. 1  225 S Van Rensselaer St, Rensselaer (0.1 mi) 2  120 W Harrison St, Rensselaer (0.1 mi) 3  200 W Washington St, Rensselaer (0.2 mi)
Production of red blood cells is controlled by erythropoietin, a hormone produced primarily by the kidneys. Red blood cells start as immature cells in the bone marrow and after approximately seven days of maturation are released into the bloodstream.lood is a specialized body fluid. It has four main components: plasma, red blood cells, white blood cells, and platelets. Blood has many different functions, including: 1  transporting oxygen and nutrients to the lungs and tissues.
Red blood cells in the urine can come from the kidney (where urine is made) or anywhere in the urinary tract (figure 1). The urinary tract includes the ureters (the tubes that carry the urine from the kidneys to the bladder), the bladder (where urine is stored), the prostate (in men), and the urethra (the tube through which urine exits the body).