The initial filtration step in the glomerulus of the mammalian kidney occurs primarily by

The correct answer is- passive flow due to pressure difference

Explanation:

The movement of water and different solute from the blood to the renal tubules or the renal corpuscles is called filtration. This filtration occurs due to the difference in the blood pressure in glomerular capillaries.

As the blood pressure increases in the glomerulus, the hydrostatic pressure also rises in the glomerulus which increases the filtration rate in glomerulus so more blood gets into glomerulus due to this pressure.  

Therefore as the blood pressure increase in the glomerulus, the filtration rate also increases. So the initial filtration step in the glomerulus occurs primarily by passive flow due to pressure difference.

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