alleryStart learning →The lungs have no muscles of their own. When do they expand?
AWhen the stomach fills with food
BWhen the blood pressure rises
CWhen the chest cavity volume increases
DWhen the heart beats faster
Answer & Solution
Correct answer: C. When the chest cavity volume increases
Lungs are pulled open passively whenever the chest cavity gets larger, as the diaphragm and rib muscles act.
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