There is a certain part of the Respiratory System called the respiratory airways. Your respiratory airways are made up of the nose, mouth, and trachea. The nose has cilia and it filters the air you breath in and warms it up. The boogers in your nose are the stuff that got filtered out. That is one reason why it is better to breath in through your nose than your mouth. The trachea also has cilia. The trachea is protected by cartilage. There is a way you can tell if the cilia in your trachea is working...you cough. When you cough you cough out all the stuff that got filtered in the trachea. The clean air finally goes to you lungs. Your lungs are very moist and spongy and if you didn't have this filtration system, you would become very ill and pass away. Obviously,now you can see why this function is important.

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