Urine is mostly water (about 95% water), however, the rest of the contents of urine can vary depending of what youâve eaten, drank, breathed or been exposed to. The remainder of urine usually consists of urea, uric acid, ammonia, hormones, dead blood cells, proteins, salts and minerals, and toxins.he urine then collects in your bladder untilâ¦ you feel the urge. As you urinate, the urine then leaves the bladder and expels from your body through your urethra. As we stated earlier, the urethra opening to expel the urine is located in different places for men and women.