Final answer:
The renal tubule, which is part of the nephron in the kidney, includes the Proximal Convoluted Tubule (PCT), Descending and Ascending Limbs of the Loop of Henle, and the Distal Convoluted Tubule (DCT), and plays a critical role in urine formation.
Step-by-step explanation:
The duct that leads away from the glomerular capsule and is divided into four regions is the renal tubule. The renal tubule is a crucial component of the nephron, which is the functional unit of the kidney. The four regions of the renal tubule are:
- Proximal Convoluted Tubule (PCT) - This is the first part of the renal tubule, adjacent to the glomerulus, located in the renal cortex.
- Descending Limb of the Loop of Henle - This segment descends into the renal medulla, forming a countercurrent multiplier osmotic gradient that is crucial for urine concentration.
- Ascending Limb of the Loop of Henle - After reaching the deepest part, the loop ascends back toward the renal cortex.
- Distal Convoluted Tubule (DCT) - The DCT is the final segment within the nephron's structure, also located in the renal cortex, before merging into the collecting ducts.
The renal tubule is surrounded by a network of capillaries, including the peritubular capillaries and the vasa recta, which are involved in the reabsorption and secretion processes that refine the filtrate into urine. Urine then passes into collecting ducts, which consolidate the filtrate from various nephrons and eventually lead to the renal pelvis.