A projecting ridge or fin on the bottom of the hull of a boat or ship that improves directional control and is often weighted for added stability. 2. The principal structural member of an aircraft, resembling a ship's keel in shape and function.
The outer, reddish region, next to the capsule, is the renal cortex. This surrounds a darker reddish-brown region called the renal medulla. The renal medulla consists of a series of renal pyramids, which appear striated because they contain straight tubular structures and blood vessels.
The kidneys are bilateral bean shaped organs, located in the posterior abdomen. They are reddish-brown in colour. The main function of the kidneys is to filter and excrete waste products from the blood.They are also responsible for water and electrolyte balance in the body.Metabolic waste and excess electrolytes are excreted by the kidneys to form urine. Urine is transported from the kidneys to the bladder by the ureters.he kidneys lie retroperitoneally (behind the peritoneum) in the abdomen, either side of the vertebral column. The left and right kidneys are located at different vertebral levels: 1  Left kidney: T11- L2. 2  Right kidney: T12 â L3 (it is lower due to the presence of the liver).