BIO E105 Lecture Notes - Lecture 23: Straight Arterioles Of Kidney, Ureter, Osmotic Concentration
Document Summary
The nephron shares important functional characteristics with the insect excretory system. Water cannot be transported actively it moves only by osmosis exert precise control over loss or retention of water and electrolytes. To move water, cells in the kidney set up strong osmotic gradients. By regulating these gradients and specific channel proteins, kidney cells. Nephrons have four major regions and are closely associated with a collecting duct: the renal corpuscle filters blood, forming a pre- urine consisting of ions, nutrients, wastes, and water. In the proximal tubule, epithelial cells reabsorb nutrients, vitamins, valuable ions, and water: the loop of henle establishes a strong osmotic gradient in the tissues outside the loop, and osmolarity increases as the loop descends. In the distal tubule, ions and water are reabsorbed. To maintain homeostasis with respect to water, more water may be reabsorbed in the collecting duct.
