The respiratory system Crossword

This printable crossword puzzle on the topic of Human Body Systems has 12 clues. Answers range from 3 to 13 letters long. This crossword is also available to download as a Microsoft Word document or a PDF.

air is inhaled through a humans?
Once our lungs fill up with air we release ?
Our lungs take in?
our nose is made up of how many cavities?
every cell in our body needs _________ to do its job
the blood carries oxygen throughout the ___________ system
_______ is a slimy liquid
each bronchi leads to one of our body's two ______
when you cough its travels at ______________mph
lungs are made up of?
the heart pumps ??
our lungs has thousands of