Excretion is a process of removing waste materials such as nitrogenous waste through excretory system is known as Excretion. Excretory system includes a pair of Kidneys; a pair of ureters, Urinary bladder and urethra to complete excretion process successfully. Excretion is carried out by one special organ in human body called Kidney. Kidney has specialized structure called nephrons for excretion. Kidney performs excretion process in three steps such as Filtration, Re absorption and secretion. Urinary bladder and urethra are mainly involved in Urination that is excretion of urine from the kidney.

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