Step by step explain excretion occurs in human beings?

 

The human excretory system is made up of two kidneys, two ureters, the urine bladder, and the urethra. 

The kidneys produce urine by removing nitrogenous waste and undesired extra substances from the circulation.

A nephron is the functional unit of the kidney that performs the basic function of filtration.

The urea generated by the liver enters the bloodstream.

When urea-containing blood enters the glomerulus, it is filtered by capillaries, separating urea and other related molecules.

Water molecules and tiny molecules of other substances can pass through Bowman's capsule's semipermeable membrane.

The solution that has accumulated in the cavity of Bowman's capsule enters the tubular portion of the nephron. 

Water molecules and other important compounds are reabsorbed into the bloodstream here.

Urine is created from the leftover solution, which contains a lot of nitrogenous waste. 

The ureters transport urine to the urinary bladder, where it is stored. 

Urine is then expelled through the urethra.