1. a. why the cell needs the item b. how the need gets to/leaves the cell c. what tissues help the cell get the need and how d. what organs help the cell get the need and how e. what systems help the cell get the need and how

2. The cell needs to release Carbon Dioxide so it can take in Oxygen. The cell turns sugar and fat into energy using oxygen. In this process it also produces Carbon Dioxide. It now has to release the Carbon Dioxide so it has room for the oxygen and so it won’t rupture.

3. When a certain part of the body is loosing energy it releases carbon dioxide to make more room for the oxygen. It sends the carbon dioxide to the blood stream and then through the lungs and out the mouth.