Science+Breathing+8

OBSERVE: Pull down slowly on the stretched balloon. What happens to the balloon inside the cup? When the stretched balloon is pulled down the inside balloon gets more air in it. Push up on the stretched balloon. What happens inside the cup? When I push up on the stretched balloon the smaller balloon loses all of it's air inside!

EVALUATE: Is there more or less space inside the cup when you pull down on the large balloon? There is more space inside the cup when I pull the bigger balloon down!

IDENTIFY: When you pull the large balloon down, what fills the extra space in the cup? When I pull the large balloon down, air fills the extra space in the cup.

COMPARE: 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. The air pressure in the balloon is similar to the air pressure in your lungs because the are built like the same way just different materials. I think that when you breath air into your lungs that you lungs will get smaller.

Chanda, if you think about your responses to the first 4 questions, you will answer differently for this last question. Do your lungs get smaller when you breathe air **in** or when you breathe air **out**? Tell me __how__ the pressure in the balloon is similar to that in your lungs.