Body+Organization+and+Homeostasis

=Body Organization =

There are levels of organizatin in the body of all animals.These levels are: **cells**, **tissues**, **organs** and **systems**.

The __**c﻿ell**__ is the basic unit of life. All animal cells contain a cell membrane, a nucleus, cytoplasm, and many organelles. Cells have different jobs depending where they are located.

﻿﻿﻿Cells with the same function can group to form **__tissues__**. There are four basic types of tissues:
 * //muscle//: allows movement
 * //connective//: provides support
 * //nervous//: controls the processes in the body
 * //epithelial//: covers inner and outer body surfaces

A group of tissues forms an __**organ**__. Each organ has specific jobs. The heart, for example, pumps blood throughout the body. Organs can work together to perform a function. When this happens you can say they belong to the same **__system__**. The stomach, the esophagus, the small intestine and the large intestine make up the digestive system.

=Homeostasis =

All systems work together to maintain an internal balance. You call this **homeost﻿asis**. Our body temperature can illustrate this. The external temperature may vary but our internal temperature is maintained stable with the help of the nervous system (through nerve cells) and the endocrine system (through hormones). These systems promote sweating when it is too hot and shivering when it is too cold. These actions restore our normal body temperature.