Salt actively leaves the ascending limb and enters the medulla, lowering its water potential. Water then leaves the descending limb via osmosis, concentrating the fluid within and creating a salty medulla that draws water from the collecting duct.
This card describes maintaining the sodium ion gradient: salt leaves the ascending limb (actively transported into the medulla), decreasing the medulla's water potential. Water leaves the descending limb by osmosis, concentrating the fluid. This creates a salty medulla that draws water from the collecting duct.
| Front | Stages for maintain of sodium ion gradient in loop of henle |
|---|---|
| Back | Salt leaves ascending limb, active transported into medulla This leads to decrease in water potential of medulla Water then leaves descending limb by osmosis and is reabsorbed by the capillaries Fluid in the descending limb becomes more concentrated as it descends into the medulla At the base of ascending limb salt diffuses out into medulla Medulla ends up very salty ( low water potential) Water moves out of collecting duct by osmosis and is absorbed into capillaries |
Learn with these flashcards. Click next, previous, or up to navigate to more flashcards for this subject.
Next card: Interstitial space region ascending descending limb loop henle
Previous card: Descending limb impermeable to salt
Up to card list: AQA Biology Flashcards