The urinary system or renal system is the organ system that produces, stores, and eliminates urine. The various components or organs of the urinary system take part in the production, storage, and then expulsion of urine from the body. In humans it includes two kidneys, two ureters, the bladder and the urethra. The female and male urinary system are very similar, differing only in the length of the urethra. Nitrogenous waste products is excreted by the urinary system, which, if not eliminated from the body, can become toxic and cause the death of an individual. Also, maintaining the volume of blood, blood pressure and blood pH, and stimulating the synthesis of red blood cells and vitamin D are its other functions. The urinary system also works with other organs, like the skin, lungs and intestines, to excrete all types of waste products generated in the body, while carrying out the vital life processes. Any kind of injury or damage to any part of the urinary system can impair the whole process of excretion, leading to accumulation of toxic substances, and giving rise to a number of health problems.