Compare and contrast the mechanics of the processes of inhalation and exhalation

Compare and contrast the mechanics of the processes of inhalation and exhalation

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Compare and contrast the mechanics of the processes of inhalation and exhalation [In common with all mammals humans ventilate their lungs by breathing in and out. This reciprocal movement of air is less efficient and is achieved by alternately increasing and decreasing the volume of the chest in breathing. The body's requirements for oxygen vary widely with muscular activity. In violent exercise the rate and depth of ventilation increase greatly: this will only work in conjunction with increase in blood flow, controlled mainly by the rich innervation of the lungs. Inadequate gas exchange is common in many diseases, producing respiratory distress.] The medulla sends motor impulses (via the phrenic nerves) to the intercostal muscles which will
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Unformatted text preview: then contract and raise the ribs and to the diaphragm which will contract (lower). In this way the thorax is enlarged and air taken into the chest. Inhibitory effects on the medulla will cause the reverse of the noted effects. During inspiration (active) the diaphragm tenses (contracts) and moves down (lowers). During exhalation (usually passive) the diaphragm relaxes and is raised. During inspiration the intercostal muscles elevate the ribs; during exhalation these muscles relax and the ribs lower themselves. With the expansion of the thorax during inspiration (inhalation) the air rushes in and the lungs inflate; they deflate with the contraction of the thorax during exhalation....
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