21. 1 O 2 diffuses through lung capillary wall. (a) Transport of oxygen ( ) 2 O 2 is carried to tissues bound to hemoglobin. 3 O 2 diffuses through tissue capillary walls . lung side body cell side hemoglobin 1 CO 2 diffuses through tissue capillary wall. (b) Transport of carbon dioxide ( ) lung side body cell side 2 CO 2 is carried to lungs. 3 CO 2 diffuses through lung capillary walls. dissolved in plasma HCO 3 – as bicarbonate bound to hemoglobin
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Notas del editor
Figure: 29-7 part a Title: The human respiratory system part a Caption: (a) Air enters through the nasal cavity and mouth and passes through the pharynx and the larynx into the trachea. The epiglottis prevents food from going down the trachea. The trachea splits into two large branches, the bronchi, which lead into the two lungs. The smaller branches of the bronchi, the bronchioles, lead to the microscopic alveoli (which are enmeshed in capillaries), where gas exchange occurs. The pulmonary artery carries deoxygenated blood (in blue) to the lungs; the pulmonary vein carries oxygenated blood (in red) back to the heart.
Figure: 29-7 part b Title: The human respiratory system part b Caption: (b) Close-up of alveoli (their interiors are shown in the cut-away section) and their surrounding capillaries. Question The nasal passages of mammals tend to follow long, complicated, winding pathways. Why are nasal passages so convoluted?
Figure: 29-10 Title: The chemistry and mechanism of gas exchange