Question
Biology Question on excretory products and their elimination
The net pressure gradient that causes the fluid to filter out from the glomeruli into the capsule is
A
50 mm Hg
B
75 mm Hg
C
10 mm Hg
D
30 mm Hg
Answer
10 mm Hg
Explanation
Solution
(i) Glomerular capillary pressure (60 mm Hg) favours filtration. (ii) The colloidal osmotic pressure (due to plasma proteins, particularly albumin) acts against filtration. Its value is 32 mm Hg. (iii) The filtrate pressure due to the glomerular filtrate filled in the Bowman's capsule also acts against filtration. Its value is 18 mmHg. Net filtration pressure = 60 - (32 + 18) mm Hg = 10 mm of Hg