ABSTRACT
Functional anatomy The gross morphological anatomy of the kidney is shown in Figure 25.1. They are retroperitoneal organs, each approximately 12cm long and 150g in weight, which lie between vertebrae T12 and L3. The basic functional unit of the kidney is the nephron (Figure 25.2), comprising the glomerulus from which fluid is filtered and its renal tubule in which the filtered fluid is converted into urine. The glomerulus is formed by a tuft of capillaries invaginating into the dilated, blind end of the tubules known as Bowman’s capsule (Figure 25.3). These capillaries are supplied by an afferent arteriole and drained by an efferent arteriole. There are about 1.3 million nephrons in each human kidney.
