Exhalation

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Exhalation (or expiration) is the movement of air out of the bronchial tubes, through the airways, to the external environment during breathing.

Exhaled air is rich in carbon dioxide, a waste product of cellular respiration during the production of ATP.

Exhalation has a complementary relationship to inhalation, the cycling between these two efforts define respiration.

Contents 1 Process 1.1 Active 2 See also 3 External links

[edit] Process

Exhalation is usually passive, but it can be active, either due to conscious control, or the demands of exercise or speech. Checking is the process of recruiting the muscles of inhalation for exhalation.

[edit] Active

During exercise, exhalation becomes an active process. Internal intercostals and abdominal muscles (Rectus abdominis, Transversus abdominis, Abdominal external oblique, Abdominal internal oblique) contract during forced expiration.

This causes rapid exhalation.

[edit] See also

[edit] External links

• MeSH Exhalation
• Dictionary at eMedicine Exhalation
• Physiology at MCG 4/4ch2/s4ch2_14

v • d • e Respiratory system, physiology: respiratory physiology

Volumes: lung volumes - vital capacity - functional residual capacity - respiratory minute volume - dead space - spirometry - body plethysmography - peak flow meter ventilation (V) (positive pressure) breath (inhalation, exhalation) - respiratory rate - respirometer - pulmonary surfactant - compliance - hysteresivity - airway resistance pulmonary circulation - perfusion (Q) - hypoxic pulmonary vasoconstriction - pulmonary shunt ventilation/perfusion ratio (V/Q) and scan - zones of the lung - gas exchange - pulmonary gas pressures - alveolar gas equation - hemoglobin - oxygen-haemoglobin dissociation curve (2,3-DPG, Bohr effect, Haldane effect) - carbonic anhydrase (chloride shift) - oxyhemoglobin - respiratory quotient - arterial blood gas - diffusion capacity - Dlco control of respiration: pons (pneumotaxic center, apneustic center) - medulla (dorsal respiratory group, ventral respiratory group) - chemoreceptors (central, peripheral) - pulmonary stretch receptors - Hering-Breuer reflex high altitude - oxygen toxicity - hypoxia