In the absence of vasopressin, this part marked with (3) reabsorbs the greatest fraction of filtered water?
Loop of Henle
This structure is Proximal tubule of nephron
- Proximal tubule is highly water permeable.
- Approximately, 65% of the filtrate is reabsorbed, driven by active transport.
- As ions are reabsorbed water follows by osmosis.
Action of vasopressin:
- Vasopressin influences water permeability only in the distal and collecting tubules.
- It has no influence over the 80% of the filtered water that is reabsorbed without control in the proximal tubule and loop of henle.