Chapter 16

Skin, Bones, and Muscles

16.1 Lesson 16.1: Organization of Your Body

Lesson Objectives

• List the levels of organization in the human body.


• Identify the four types of tissues that make up the body.


• Identify 12 organ systems.


• Describe how organs and organ systems work together to maintain homeostasis.

Check Your Understanding

• What is a cell?


• What are some of the differences between a prokaryotic cell and an eukaryotic cell?


• What are some of the basic functions of animal cells?

Introduction

The men inFigure16.1have just jumped into freezing icy water. They are having fun, but
imagine how cold they must feel! One minute their bodies were wrapped in warm clothes,
the next, they were dunked in freezing water. Their bodies are now working hard to adapt
to the sudden great change in temperature. The ability of the body to maintain a stable
internal environment in the response to change is calledhomeostasis. Homeostasisallows
your body to adapt to change, such as jumping into cold water, running in hot weather, or
not getting enough food when you are hungry. Homeostasis is an important characteristic
of living things.