Urine formation involves:
$I.$ Glomerular filtration
$II.$ Selective reabsorption
$III.$ Tubular secretion
Choose the correct option for the above statements.

$GFR$ (Glomerular Filtration Rate) is the amount of filtrate formed by the kidney per

Study the following statements and select the correct answer from the given options.
$i$. Diameter of afferent arteriole being smaller raises glomerular pressure for ultrafiltration.
$ii$. The colloidal osmotic pressure of blood is about $30 \ mmHg$ that opposes ultrafiltration.
$iii$. The arrangement of podocytes favours ultrafiltration.

The glomerular filtrate consists of

Composition of urine:
$I.$ Water ...$A\%$
$II.$ Urea ...$B\%$
$III.$ Uric acid ...$C\%$
$IV.$ Salt ...$D\%$
Choose the right options for $A, B, C$ and $D$ from the given options.

Which one of the following statements in regard to the excretion by the human kidneys is correct?