Ureter- The ureter (one for each kidney) is a long, straight tube with muscle walls. This tube’s epithelium is stratified, transitional epithelium. Underneath the epithelium is a thick, fibroelastic lamina propria.

Kidney- The kidneys filter waste and excess water from the circulation (through urine) and aid in the balance of substances in the body (such as sodium, potassium, and calcium). The kidneys also produce hormones that assist regulate blood pressure and stimulate the production of red blood cells in the bone marrow. Simple cuboidal epithelium is found in glandular tissue and in the kidney tubules.

Urethra- The urethra is the tube through which urine leaves the body. It empties urine from the bladder. The female urethra is lined by stratified columnar epithelium and has a few tiny mucosal glands that release mucus. It is attached to the vaginal anterior wall by an external layer of fibrous connective tissue.