Kidney stones are composed of ..........

The artificial kidney is designed according to the principle of

Kidney crystals (stones) are solid clusters of:

$A -$ Malfunctioning of kidneys can lead to accumulation of urea in blood,a condition called uremia.
$R -$ Blood drained from a convenient artery is pumped into a dialyzing unit after adding an anticoagulant like heparin.

Nephritis is caused by

Based on the statements regarding dialysis, choose the correct answer from the options given below.
Statement-$I$: Dialysis is regarded as a 'holding measure' until a renal transplant is performed.
Statement-$II$: Sometimes dialysis is not a supportive measure in those for whom a transplant is inappropriate.