Description: The respiratory system takes in oxygen by
inhalation and releases carbon dioxide by exhalation. The breathing system
consists of the upper and lower respiratory tracts including the lungs.
Oxygen taken into the alveoli of the lungs is absorbed by the blood and
exchanged for carbon dioxide. A mucus lining of the upper respiratory tract
prevents the entry of foreign particles and pathogens. A muscle underneath
the lungs, called the diaphragm, as well as the intercostal muscles along
the ribcage, aid in the contraction and relaxation of the lungs during
breathing. |
