Cheryl Butler

The Respiratory System:

The primary function of the lungs is to exchange gases, taking in oxygen and expelling carbon dioxide. During inhalation, the diaphragm contracts and chest muscles expand, creating a vacuum-like effect that draws air into the lungs. During exhalation, the muscles relax and the lungs return to their normal size, pushing out the air. When you inhale, air enters through the nostrils and passes through the nasal cavity, which is lined with mucus-producing cells. This mucus contains lysozymes, enzymes that help kill bacteria. The mucus also coats nose hairs, which can trap dust, pollen, and bacteria, forming small clumps known as boogers.