"Excretory system of Human being

 Excretory System:

The life of each organism depends on certain basic processes. Excretion is one of them. Different organisms follow different parts of excretion. In complex organisms including humans, there is a specialized system for excretion called the human excretory system (byjus.com).

For example, aquatic animals excrete waste in the form of ammonia, while birds and insects excrete mainly uric acid.

Excretory System Organs

· kidneys

· ureters

· urinary bladder

· urethra

Kidneys

Kidneys are bean-shaped structures located on either side of the backbone 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.

The kidneys have an inner-concave structure. The blood vessels, ureters, 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 inner to the hilum, has many projections known as calyces.

Structure of the kidneys

The structure of the kidneys is explained below.

· Capsule

· Nephrons

· Henle’s loop

· Ureter

· Urinary Bladder

· Urethra

· Excretion in humans

Mechanisms of excretion in humans

The process of excretion in humans involves the following steps:

· Urine Formation

· Tubular Reabsorption

· Secretion

· Glomerulus - filters the blood

The Human excretory system

• The human excretory system includes organs that facilitate the removal of nitrogenous wastes from the body. The main excretory organs include the kidney, ureter, urinary bladder, and urethra.
• Kidneys filter blood and urine is obtained.
• Urine passes to the urinary bladder via the ureter and is expelled out of the body. This is known as micturition.
• Kidneys also regulate the osmotic pressure in a mammal’s blood through excessive purification and filtration. This is known as OSMoregulation.