Question

Reason for development of filtration process.

Answer 1

$\sf{\underline{Development\:of\:filtration\:process:}}$

Blood flows through glomerular under a pressure. This pressure is due to two reasons:

$\bullet$ Larger diameter of afferent arteriole as compared to smaller diameter of efferent arteriole.

$\bullet$ Natural arterial pressure is caused by pumping activity of heart.


$\sf{\underline{What\:is\:GHP?}}$

Blood pressure in glomerular blood is about 60 mm Hg, this is called glomerular hydrostatic pressure (GHP).


$\sf{\underline{What\:is\:BCOP?}}$

Osmosis concentration of proteinaceous content of glomerular blood is equivalent to 30 mm of Hg, this is called blood colloidal osmotic pressure (BCOP).


$\sf{\underline{What\:is\:CHP?}}$

Pressure of interstitial fluid and pressure of renal filtrate is collectively called capsular hydrostatic pressure (CHP = 20 mm Hg).


$\sf{\underline{What\:is\:GFP?}}$

The pressure being exerted on glomerular blood for undergoing filtration is called glomerular filtration pressure (GFP). It is about 10-25 mm Hg.

$\sf{GFP = GHP - (BCOP + CHP)}$

$\sf{GFP = 60 - (30 + 20)}$

$\sf{GFP = 60 - 50}$

$\sf{GFP =}$ $\boxed{10 \: mm \: Hg}$


$\sf{\underline{\underline{Note:}}}$

$\sf{\underline{What\:is\:GFR?}}$

$\bullet$ The amount of the filtrate formed by the kidneys per minute is called glomerular filtration rate (GFR).

$\bullet$ GFR in a healthy individual is approximately 125 ml/min, i.e., 180 litres per day.