Also called: kidney, renal anatomy
The kidneys are a pair of bean-shaped organs that lie behind the peritoneum on either side of the spine at about T12 to L3. They filter blood, regulate fluid, electrolyte and acid-base balance and produce urine, which drains through the ureters to the bladder. The renal arteries branch directly from the aorta.
| Location | Retroperitoneal, either side of the vertebral column; the right kidney lies slightly lower than the left because of the liver. |
|---|---|
| Structure | Renal cortex and medulla, renal pyramids, minor and major calyces, renal pelvis, hilum; nephrons as the functional unit. |
| Function | Filters blood, regulates fluid and electrolytes, excretes waste, produces erythropoietin and renin, activates vitamin D. |
| Blood supply | Renal arteries from the abdominal aorta; renal veins drain to the inferior vena cava. |
| Innervation | Renal plexus, mainly sympathetic (T10-L1). |
3D model: BodyParts3D (CC BY 4.0), adult male reference anatomy. Highlighted structure shown with nearby bones for context.
The kidneys receive about a fifth of cardiac output. The adrenal glands sit on top of each kidney within the same renal fascia.
Retroperitoneally on either side of the spine, at roughly the T12 to L3 levels.
The functional unit of the kidney, consisting of a glomerulus and a tubule.
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