The inside of your nose is called the nasal cavity. A mucous membrane lines your nasal cavity and it helps keep your nose moist. Little hairs inside your nasal cavity help filter the air you breathe in and block dirt and dust from getting into your lungs.
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I think it is carbohydrate metabolism
8. Arteries carry oxygenated blood from the heart to the rest of the body, while veins carry deoxygenated blood from the body, back to the heart. Arteries are thick and muscular, while veins aren't as thick, and they have valves.
Bacteria !!!!!!!!!!!!!!!!!!!!!