These materials in our bodies are very important. Cells, Tissue, Organs, and our Systems, are what make up your body and what help you stay alive. Within some of these topics are many different parts. For the Organs there is the heart, brain, Lungs and so forth. In the systems their are, Respiratory, Digestive, Nervous, and many more that probably won't fit on this page. As I have said before These parts help us stay alive.