Crossword Puzzle Respiratory System CrosswordOnline version Test your knowledge of the anatomy involved in breathing and gas exchange. by Diana Lucia Muñoz Canizales 1 A muscle that separates the chest from the abdomen and aids in breathing. 2 Tiny air sacs in the lungs where gas exchange occurs. 3 The windpipe that connects the throat to the lungs. 4 One of the two main branches of the trachea leading to each lung. 5 Small air passages that branch off from the bronchi within the lungs. 6 An organ responsible for the exchange of oxygen and carbon dioxide. 7 Small blood vessels that facilitate the exchange of gases with alveoli. 8 The process of moving air in and out of the lungs. 4 2 5 1 7 6 8 3