Respiratory System

3. The product of fermentation used in beer and wine production.
4. Small air sacs that allow gaseous exchange to occur via diffusion.
6. The addictive component of cigarette smoke that increases blood pressure.
9. The product (alongside ATP) of anaerobic respiration in humans.
11. Smaller divisions of the bronchi which lead to the alveoli.
12. These tiny blood vessels surround the alveoli and maintain a steep concentration gradient.
13. The volume of oxygen needed to break down lactic acid into water and carbon dioxide.

1. The chest cavity where the lungs and heart are found.
2. Process of anaerobic respiration in yeast. This forms carbon dioxide and ethanol as waste products.
5. Another term to describe breathing in/out.
7. Name of the membranes which prevent the lungs rubbing directly on the ribs and therefore reduce friction.
8. The two tubes branching off the trachea which allow air to enter the lungs.
10. The muscular sheet that separates the thorax and abdomen, which contracts and flattens during inhalation.