The human excretory system organs include: A pair of kidneys, A pair of ureters, A urinary bladder, and A urethra
Kidneys:-
Kidneys are bean-shaped structures located on either side of the backbone (between transverse processes of T12-L3 vertebrae) and are protected by the ribs and muscles of the back. Each human adult kidney has a length of 10-12 cm, a width of 5-7 cm, and weighs around 120-170g.
It is the main excretory organ in humans. The kidney filters the blood and excretes waste along with water in the form of urine.
The kidneys have an inner concave structure. The blood vessels (renal artery and renal vein), ureter, and nerves enter the kidneys through the hilum, which is a notch at the inner concave surface of the kidney. The renal pelvis, a large funnel-shaped space present inner to the hilum, has many projections known as calyces.
Ureter:-
A pair of thin muscular tubes called the ureter comes out of each kidney extending from the renal pelvis. It carries urine from the kidney to the urinary bladder.
Urinary bladder:-
It is a muscular sac-like structure, which stores urine. The urinary bladder is emptied by the process of micturition, i.e. the act of urination.
Urethra:-
This tube arises from the urinary bladder and helps to expel urine out of the body. In males, it acts as the common route for sperms and urine. Its opening is guarded by sphincter muscles.