Question

Read the following statements and choose the correct option
i. Glomerular filtration rate in a healthy individual is about 180 ml/day
ii. All constituents of plasma pass into the lumen of Bowmans capsule
iii. 70 - 80% of electrolytes and water are reabsorbed in PCT
iv. Angiotensin II increases the glomerular blood pressure and GFR
v. Countercurrent systems contribute to concentrating the filtrate

• A. i and ii only are correct
• B. v along is correct
• C. ii, iii and iv are correct
• D. iii, iv and v are correct
• E. i, iv and v only are correct

Answer 1

The correct option is D iii, iv and v are correct

1) PCT is lined by Cuboidal epithelium with brush border. It increases the surface area for reabsorption. Hence 70 - 80% of electrolytes and water are reabsorbed in PCT.

2) Angiotensin II is a powerful vasoconstrictor. Hence it increases the glomerular blood pressure and thereby GFR.

3) The flow of filtrate in the two limbs of Henle’s loop is in opposite directions and thus forms a counter current. The flow of blood through the two limbs of vasa recta is also in a countercurrent pattern. The proximity between the Henle’s loop and vasa recta, as well as the countercurrent in them, hence Countercurrent systems, contribute to concentrating the filtrate

So, the correct answer is 'iii, iv and v are correct'.