Crossword Puzzle The respiratory systemOnline version A funny activity for all. by Mateo Sánchez-Navarrete 1 to tubes at the lungs 2 a muscle that is under the lungs 3 little sacs of air when it changes the CO2 with The O2 4 a tube that send the air to the lungs 5 you can breath by the nose and the _____ 6 big organ were you store air 7 you use it to breath 2 5 6 7 3 1 4