Question

how does excration occur in human beings

Answer 1

Humans have two kidneys and each kidney is supplied with blood from the renal artery. The kidneys remove from the blood the nitrogenous wastes such as urea, as well as salts and excess water, and excrete them in the form of urine. ... The filtrated blood is carried away from the kidneys by the renal vein (or kidney vein).

Answer 2

Humans have two kidneys and each kidney is supplied with blood from the renal artery. The kidneys remove from the blood the nitrogenous wastes such as urea, as well as salts and excess water, and excrete them in the form of urine. ... The filtrated blood is carried away from the kidneys by the renal vein (or kidney vein).