Excretion: 1 Mark
Components: 2 Marks
Functions: 2 Marks
During various activities which are performed within the cells in the body, certain by-products are produced. Some of these products are toxic and are required to be thrown out. This is the reason why excretion is required.
The various components of the excretory system of humans include a pair of kidney, ureter, urinary bladder and the urethra.
Kidneys are the structures where the purification of blood occurs. From the kidneys, the urine goes into the urinary bladder through tube-like structures called ureters. It is stored in the urinary bladder and is passed out through the urinary opening at the end of a muscular tube called urethra.