When air pressure inside the lungs is less than air pressure in the atmosphere .....

PULMONARY PHYSIOLOGY

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Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]

When air pressure inside the lungs is less than air pressure in the atmosphere ____

A	Air moves into the lungs
B	Air moves out of the lungs
C	Either A or B
D	None of the above

Explanation:

Detailed explanation-1: -Because of the pressure gradient between the lungs and the atmosphere, the air moves into and out of the lungs. Inspiration occurs if the pressure within the lungs (intra-pulmonary pressure) is less than the atmospheric pressure i.e. there is a negative pressure in the lungs with respect to atmospheric pressure.

Detailed explanation-2: -When alveolar pressure becomes greater than atmospheric pressure, expiration occurs, and air flows out of the alveoli.

Detailed explanation-3: -When the air pressure within the alveolar spaces falls below atmospheric pressure, air enters the lungs (inspiration), provided the larynx is open; when the air pressure within the alveoli exceeds atmospheric pressure, air is blown from the lungs (expiration).

There is 1 question to complete.