how+breathing+works+investigation

Pull down slowly on the stretched balloon. What happens to the balloon inside the cup? ** The balloon on the inside of the cup is expanding with air.
 * OBSERVE:

The space inside gets smaller. Yes, but what happens to the balloon inside the cup?
 * Push up on the stretched balloon. What happens inside the cup? **

Is there more or less space inside the cup when you pull down on the large balloon? ** More space.
 * EVALUATE:

When you pull the large balloon down, what fills the extra space in the cup?** The balloon that is filled with water. Where did the water come from? Did you read the question carefully?
 * IDENTIFY:

How is the air pressure in the balloon similar to the air pressure in your lungs? Write down what you think happens when you breathe air into your lungs.** When you breath the lungs expand like when you stretch the inside of the cup an when you push air out it is like when you push the balloon in. How is the air pressure similar?
 * COMPARE: