Comprehension STOP Use your dictionary to find out the meaning of the bold words and phrases below.


! How Lungs Work What are your lungs?


Your lungs make up one of the largest organs in your body. They work with your respiratory system to allow you to take in fresh air and oxygen and get rid of stale air and carbon dioxide.


Where are they located?


Your lungs are located in your chest. You have two lungs, but they are not the same size, the lung on the left side of your body is a bit smaller than the lung on the right. This extra space on the left leaves room for your heart.


How are they protected?


Your lungs are protected by your rib cage, which is made up of 12 sets of ribs. These ribs go around your lungs to keep them safe.


You can’t see your lungs but it’s easy to feel them in action. Put your hands on your chest and breathe in (inhale) very deeply. You will feel your chest getting slightly bigger. Now breathe out the air (exhale) and feel your chest return to its regular size.


What do they look like?


From the outside, lungs are pink and a bit squishy, like a sponge. Each lung has about 30,000 tiny tubes called bronchioles. Each bronchiole is about the same thickness as a hair. At the end of each bronchiole is a special area of tiny air sacs called alveoli.


What do they do?


You inhale air through your mouth and nose, and the air moves down your trachea. On the way down the trachea, tiny hairs called cilia move gently to keep mucus and dirt out of the lungs. The air then goes into your lungs. Oxygen from the air passes into your blood. All the cells in your body need oxygen. When your body has taken all the oxygen it needs, it gives out waste and carbon dioxide. This leaves your body as you exhale. You can feel the air leaving your body by putting your hand in front of your mouth or nose as you breathe out.


Alveoli 80


Nasal cavity


Trachea Bronchiole


Right lung


Left lung


Mouth


Unit 14 | Explanatory Text 1


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