Which one of the following statements regarding water reabsorption in the tubules?
A i.e. The bulk of water reabsorption occurs secondary to Na+ reabsorptionProximal convoluted tubule reabsorbs approximately 50-60% of water (bulk of water), which is secondary (obligatory) to Na+ reabsorptionQReabsorption of waterObligatory reabsorption Absorption of water in proximal tubules secondary to Na+ reabsorptionQ - Absorption of water in renal tubules independent of plasma osmolality (irrespective of water balance) - Filtered water is reabsorbed isoosmotically & is independent of ADH levels. Facultative reabsorptionAbsorption of water in distal tubules and collecting duct in presence of ADHQ- Absorption of water depends on variation in plasma osmolalityNormally DCT and collecting ducts are not permeable to water but in presence of ADH, these segments become permeable.* Thick ascending limb of Henle & early distal tubule are both impermeable to waterQ & no reabsorption occurs irrespective of water balance.
The bulk of water reabsorption occurs secondary to Na" reabsorption.
Majority of facultative reabsorption occurs in proximal tubule.
Obligatory reabsorption is ADH dependent
20% of water is always reabsorbed irrespective of water balance