Sample essay on our Excretory System

Excretion is the removal from the body of the toxic waste products ₀f metabolism. In human beings skin, lungs, liver and kidney are the organs involved in the excretory system.

Skin–

In human beings small amount of urea, salts, lactic acid and other metabolic wastes of most body cells are eliminated in the form of sweat glands through skin.

Lungs-

Human beings have a pair of lungs. They help in the elimination of carbon dioxide (a gaseous waste) from the body by ^halation.

Liver–

The liver is the largest gland in the human body. Metabolic activities in the body result in the production of poisonous substances. These are carried to the liver and converted into less toxic substances

Kidney-

It is the chief excretory organ in the human being, There are two kidneys in the human body. Each kidney is made up of numerous coiled tubules known as nephrons. Each nephron is the kidney. The kidneys collect the excretory products and eliminate them in the form of urine. The urine is released periodically outside via the urethra In case of the poor functioning of the kidney, affected person is kept on dialysis.

The skeleton system of the body comprises the bones and It provides a solid and rigid shape to the body. These bones are called the organs of the skeleton system. The total number of bones in the human being is 206. A new born baby has 300 bones, out of which 94 bones fuse together as it grows.

The skeleton system of the body has been classified into seven important categories.

Skull Bones–

It is also known as cranium or Brain Box. It ha⁵ eight bones.

Facial Bones-

The portion below the skull Is facial bones which are fourteen in numbers.

Bones of the Trunk–

The most important bone of the trunk is vertebral column which is also known as central part of the skeleton. The vertebral column has 33 bones. There is a spinal cord inside vertebral column. Thorax which is protecting casing for the lun9⁵ heart consists of one sternum (breast bone) and 24 ribs.

Bones of the Hand–

Each arm has 30 Individual bones. The most important bones of the arm are Scapula, Ulna and

Bones of the Leg–

Each leg consists of 30 bones. The most Important bones of the leg are Femur, Tibia, Fibula, Patela, Tarsus.

The largest bone of human body is femur in the thigh.

The shortest bone in the human body is stapes bone in the middle ear.