Which of the following must occur for air to enter the lungs during inhalation (inspiration)?
A) The principal muscles of inhalation (inspiration) contract.
B) The volume of the lungs increase.
C) The pressure in the lungs falls below atmospheric pressure.
D) all of these choices.

Question

Quizplus · Accepted Answer

During inhalation, the principal muscles of inhalation contract, increasing the volume of the lungs. This increase in volume leads to a decrease in pressure inside the lungs compared to the atmospheric pressure, allowing air to flow into the lungs.

Which of the Following Must Occur for Air to Enter