Human urine is usually acidic because

The $Duct$ of $Bellini$ is concerned with

Which of the following is not reabsorbed through the $\text{PCT}$?

The loop of Henle is located in the $.......$.

The maximum amount of electrolytes and water $(70-80\ \%)$ from the glomerular filtrate is reabsorbed in which part of the nephron?

$I.$ Reabsorption of water occurs passively in the initial segment of nephron.
$II.$ Nitrogenous wastes are absorbed by active transport.
$III.$ Conditional reabsorption of $Na^{+}$ and water takes place in $DCT$.
$IV.$ $DCT$ reabsorbs glucose.
$V.$ $DCT$ is capable of selective secretion of $H^{+}$,$K^{+}$ and $NH_{3}$ to maintain $pH$ and $Na^{+}-K^{+}$ balance in blood.
$VI.$ Substances like glucose,amino acids,$Na^{+}$,etc.,in the filtrate are reabsorbed actively.
Choose the option with incorrect statements.