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Alveoli, Alveoli ducts, Respiratory Bronchioles (Respiratory Zone)

Alveoli, Alveoli ducts, Respiratory Bronchioles (Respiratory Zone)


True respiration begins in the smallest bronchioles (respiratory bronchioles). They branch into alveolar ducts and finally into the tiny alveoli. They look like tiny bunches of grapes. This is where gas exchange happens. The capillaries carrying oxygen lie right up against the alveoli and form the respiratory membrane. Across this membrane the oxygen is traded for carbon dioxide. Respiration has occurred.



Assess Respiratory System comprehension with the Mutiple Choice Test.

Study the Respiratory System Diagram, then test your knowledge with the Respiratory System Labeling.

Organs of the Respiratory System

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