Soon, seemingly healthy smokers could inhale the gas in a new MRI technique to explore early signs of emphysema and asthma.
Oxygen goes in, carbon dioxide goes out. Sounds simple enough, but your respiratory system — composed of your lungs, trachea, sinuses, and sundry microscopic helpers — works a grueling 24/7 job just to keep your blood oxygenated, and your body alive. Learn all about the air you breath (and the respiratory organs that make it possible) here.
The virus infects peoples' lungs, but too deeply to be coughed or sneezed at another potential victim.