Sunnyboy

The human body is a complex biological system involving cells, tissues, organs, and systems all working together to make up a human being. From the outside, the human body can be divided into several main structures. The head houses the brain which controls the body. The neck and trunk house many important systems like the heart and lungs. The arms and legs allow the body to move in the world.

Cells[edit | edit source]

The body is made up of cells. Cells are the smallest units of life that can replicate independently, and are often called the "building blocks of life". The body contains trillions of cells, the basic unit of life. Cells group together to form tissues, which in turn group together to form organs.

Tissues[edit | edit source]

Tissues are groups of cells that have a similar structure and act together to perform a specific function. There are four basic types of tissue in the body: epithelium, connective tissue, muscle tissue, and nervous tissue.

Organs[edit | edit source]

Organs are collections of tissues grouped together performing a common function. Organs are present in all higher biological organisms, in particular they are not restricted to animals, but can also be identified in plants. Examples of organs include the heart, lungs, brain, eye, stomach, spleen, bones, pancreas, kidneys, liver, intestines, skin, uterus and bladder.

Systems[edit | edit source]

Systems are formed of organs working together to perform complex functions. For example, the digestive system, which includes organs such as the stomach and intestines, breaks down food into its nutrient components.

Health and Disease[edit | edit source]

Health is the state of the body, where it can function optimally, with vigor and alertness, without evidence of disease or abnormality. Disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs.

Medicine[edit | edit source]

Medicine is the science and practice of establishing the diagnosis, prognosis, treatment, and prevention of disease. Medicine encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness.