| Both kidneys are the same in appearance, structure and function. Blood supply into the kidneys is essential as one of the main roles of kidneys is to clean blood from wastes! It is ensured by the renal artery and then the renal vein transports blood out and back into the circulation. Kidneys are composed of 2 main parts: the outer part, called the “cortex” and the inner part called the “medulla” which is composed of structures which look like small pyramids. Each kidney contains about one million tiny functional units, called nephrons, which go across the kidney structure from the cortex to the medulla, and is surrounded by a network of small blood vessels. The nephrons are the filtering units of the kidneys. |
Did you know?
The kidneys receive 1000 to 1200 mL of blood per minute, which is a huge amount compared to their small size: it represents about 20% of blood volume, although they represent only about 0.5% of body weight! |
How do kidneys work?

