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.
When kidney is damaged, red blood cells will be leaked into the urine. When the amount of red blood cells is much more, the color of urine will become dark brown. Besides, if there is kidney stone in your body, which can lacerate the uroepithelium, leading to much more blood in the urine.So the urine presents dark brown. All in all, kidney failure can cause dark brown urine.hen kidney is damaged, red blood cells will be leaked into the urine. When the amount of red blood cells is much more, the color of urine will become dark brown. Besides, if there is kidney stone in your body, which can lacerate the uroepithelium, leading to much more blood in the urine.