Question

Why r human lungs said to be negative pressure lungs?

Answer 1

Dear student,

Human lungs are negative pressure lungs ​because the pressure created during inspiration in the lungs is negative with respect to the atmospheric pressure. Intercostal muscles contract and dome shape of diaphram flattens which decreases pressure inside the chest cavity and volume of the chest cavity increases. This creates pressure difference which forces air to move inside the lungs from outside.

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