Kidneys are 4 to 5 inch organs that are located on either side of the back at the level of the lowest ribs. Kidneys are covered with a layer of fiberous tissue called the capsule. This covering is similar to the covering of a hot dog. The kidney is surrounded by fat (Gerota's fat). This fat is contained within a second covering called Gerota's fascia. The adrenal gland which is an organ that produces hormones to maintain blood pressure and help us in times of physical stress is located adjacent to the top of the kidney within Gerota's fascia.
The function of the kidney is to help clear the blood of waste products and excess fluid. The kidney is made of two parts: the parenchyma and the collecting system. The parenchyma is the solid outer part of the kidney that filters the blood and creates droplets of urine. The collecting system is the hollow inner part where the droplets come together and are then transported to the bladder by a thin long tube called the ureter.