Exhalation

INTERCOSTAL MUSCLES Inhalation and exhalation make up 1 breath Internal intercostal muscles External intercostal muscles Sternum Inhalation ? Also termed inspiration ? Diaphragm contracts and flattens. ? Internal intercostal muscles relaxes ? While the external intercostal muscles contract ? The rib cage moves up and out. ? Enlarging the thoracic cavity and decreases the air pressure within. ? Air from the surrounding enters the lungs Exhalation ? Also termed expiration ? Diaphragm relaxes and arch upwards. ? Internal intercostal muscles contracts ? While the external intercostal muscles relaxes ? The rib cage moves down and in. ? Air is forced out of the lungs Summary

THE ?LUNG ? MODEL ? OBJECTIVES ?? To create a lung model to show the effects of inhalation and exhalation and the effects of respiratory diseases on the function of lungs. PARTS OF THE RESPIRATORY SYSTEM 1. ?Trachea ? 2. ?Lungs ? 3. ?Diaphragm ? RECAP ?I: ?INHALATION ? 1.?Diaphragm ? contracts ?and ? ?a?ns ? 2.?Rib ?cage ?moves ?up ? and ?out ? ? ?? Thoracic ?cavity ? enlarges ? ?? Lower ?pressure ? within ?the ?lungs ? ?? Air ?enters ?the ? lungs ? RECAP ?II: ?EXHALATION ? 1.?Diaphragm ?relaxes ? and ?moves ?up ? 2.?Rib ?cage ?moves ? ? down ?and ?in. ? ? ?? Rib ?cage ?presses ? on ?the ?lungs ? ?? Air ?is ?forced ?out ?