The net pressure gradient that causes the fluid to filter

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The net pressure gradient that causes the fluid to filter out of the glomeruli into the capsule is

1. 50 mm Hg
2. 75 mm Hg
3. 20 mm Hg
4. 30 mm Hg

Correct Option: C

(i) Glomerular capillary pressure (45 mm Hg) favours filteration.
(ii) The colloidal osmotic pressure (due to plasma proteins, particularly albumin) acts against filteration. Its value is ~20 mmHg.
(iii) The filterate pressure due to the glomerular filterate filled in the Bowman’s capsule also acts against filteration. Its value is ~10 mmHg.
Net filteration pressure
= 45 – (20 + 10) mm Hg
= 15 mm of Hg (10 – 20 mm of Hg)