Questions: Lungs and Breathing

Question 1

What gas does your body need from the air you breathe in?

• A. Carbon dioxide
• B. Nitrogen
• C. Oxygen
• D. Helium

Answer: (C)

Your body needs oxygen from the air. When you breathe in, air goes into your lungs, and the lungs pull out the oxygen and put it into your blood. Your blood then carries the oxygen to every part of your body.

Question 2

You have to think about breathing or it will stop.

• T. True
• F. False

Answer: False

Breathing happens automatically. Your brain controls your breathing without you having to think about it. That is why you keep breathing while you sleep, while you are distracted, and even when you are not paying attention to it at all.

Question 3

Why do you breathe faster when you exercise?

Model answer: When you exercise, your muscles need more oxygen for energy. You breathe faster to bring in more air so your lungs can give your blood more oxygen to deliver to your muscles.

Exercise makes your muscles work harder, and working muscles burn through oxygen quickly. Breathing faster brings more air into your lungs, which means more oxygen gets into your blood, which means more oxygen reaches your muscles. Your heart also beats faster to pump that oxygen-rich blood more quickly.