Excretion — Bio Zoology STD 11 — Question

Renal calculi, also called renal stone or nephrolithiasis, is the formation of hard stone-like masses in the renal tubules of the renal pelvis. It is mainly due to the accumulation of soluble crystals of salts of sodium oxalates and certain phosphates. This results in severe pain called “renal colic pain” and can cause scars in the kidneys. Renal stones can be removed by techniques like pyelolithotomy or lithotripsy.