Featured Article: Why do we say 'bless you' or 'gesundheit' when people sneeze?
Many of us offer a blessing when someone sneezes, and we don't even know why. Why does a sneeze get a "bless you" when a cough goes unanswered?" See more »
The respiratory system includes the nose, throat, larynx, trachea, bronchi, and lungs. Discover how the respiratory system supplies blood with necessary oxygen and relieves it of the waste product carbon dioxide.
Many of us offer a blessing when someone sneezes, and we don't even know why. Why does a sneeze get a "bless you" when a cough goes unanswered?" See more »
You breathe in and out anywhere from 15 to 25 times per minute without even thinking about it -- it just happens naturally. Learn all about your lungs, various conditions and diseases, and what makes the breath of life so crucial.
See more »Many of us offer a blessing when someone sneezes, and we don't even know why. Why does a sneeze get a "bless you" when a cough goes unanswered?"
See more »The respiratory system keeps us alive by oxygenating the blood in our bodies. This animation illustrates how the various pieces of the respiratory system work together.
See more »Coughing is the mechanism for clearing the breathing passages of unwanted irritants. This animation illustrates what happens during the coughing reflex.
See more »Breathing moves air in and out of the respiratory system. This animation illustrates how oxygen is carried to the blood as a result of inhalation and carbon dioxide is removed from the body during exhalation.
See more »You breath all day, every day. How much oxygen does this process consume?
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