The image shows the urinary tract. Two kidneys are located on either side of the spine near the bottom of the rib cage. Each kidney connects to a ureter via the renal pelvis and calyx. The ureters run down the body to connect to the bladder, which is located in the pelvic cavity in front of the rectum, and directly above the prostate in men, and under the uterus in women. The urethra extends from the bladder to allow urine to exit the body.

The bladder wall is composed of several layers. The inside of the bladder is lined with a layer of cells called the urothelium. The lamina propria separates this layer from the bladder wall muscles (muscularis propria), which are surrounded by perivesical fat, and finally the peritoneum.

Copyright 2004 American Society of Clinical Oncology. Robert Morreale/Visual Explanations, LLC.