Revision

6. A thin, valvelike structure that covers the glottis during swallowing, preventing the entrance of food and drink into the larynx.
7. The act of taking in breath. Inhalation results from the negative pressure in the lungs caused by contraction of the diaphragm, which causes it to move downwards and to expand the chest cavity.
8. A partition separating the abdominal and thoracic cavities. Involved in respiration.
9. The act of breathing out air. During exhalation, the diaphragm relaxes and moves upward, causing compression of the lungs and an outward flow of air.
11. The tube or cavity, with its surrounding membrane and muscles, that connects the mouth and nasal passages with the esophagus.
13. The two main branches of the trachea.
14. A muscular structure at the top of the trachea that holds the vocal cords.

1. The air cells located in the lungs.
2. System The framework of the body, consisting of bones and other connective tissues, which protects and supports the body tissues and internal organs.
3. The structures composing the skeleton of a vertebrate.
4. System The system by which oxygen is taken into the body and an exchange of oxygen and carbon dioxide takes place.
5. artery supplies blood to the heart muscle tissue.
10. The tube in humans extending from the larynx to the bronchi. Also known as the windpipe.
12. The movable or fixed places or parts where two bones or elements of a skeleton join
14. One of the two saclike respiratory organs located in the thorax.