The structure responsible for production, transportation, storage and excretion of urine form the urinary tract. Kidney, ureters, bladder and urethra are structures involved in urine formation and excretion process. Kidney filters nearly 3 ounces of blood, removes waste materials every minute. When these get infected with entry of any micro organism or any other pathological condition, then the person gets urinary tract infection (UTI). Causes and symptoms Urinary tract infections are more common in women than men because of the small size of the urethra (4cms) and also because of the squatting position of voiding.