Nasal Cavity Say: nay-zul kah-vih-tee The nasal cavity is the inside of your nose. It is lined with a mucous membrane that helps keep your nose moist by making mucus so you won't get nosebleeds from a dry nose. There are also little hairs that help filter the air you breathe in, blocking dirt and dust from getting into your lungs. Back to Articles Related Articles Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.