These anatomical structures are the following: 1. The urine itself which serves as an antiseptic, washing potentially harmful bacteria out from the body during normal urination 2. The ureters join into the bladder in a manner designed to prevent urine from backing up into the kidney when the bladder squeezes urine out through the urethra. 3. The prostate gland in men that secretes infection-fighting substance. 4. The immune system defenses and antibacterial substance in the mucous lining of the bladder eliminate many organisms. 5. The vagina of a healthy women, it is colonized by lactobacilli, a beneficial microorganisms that maintain a highly acidic environment (low pH) that is hostile to other bacteria. It also produces hydrogen peroxide, which help eliminate bacteria and reduces the ability of Escherichia coli (E. coli) to adhere to vaginal cells that is the major bacterial culprit in urinary tract infection.
