PATHOLOGY

Detailed explanation-1: -What is glomerular filtration? Glomerular filtration is the first step in making urine. It is the process that your kidneys use to filter excess fluid and waste products out of the blood into the urine collecting tubules of the kidney, so they may be eliminated from your body.

Detailed explanation-2: -So, the correct answer is ‘Active transport across the walls of proximal convoluted part’.

Detailed explanation-3: -Example-small ions like sodium and potassium pass freely but, haemoglobin and albumin have practically no permeability. Thus glomerular filtration is non selective as, though all substances must move through the glomerular membrane i.e. plasma and dissolved substances but no blood cells and large blood proteins.