During lung inflation Multiple Choice surfactant is found in the pleural cavity. the lungs cling to the internal surface of the chest wall as it expands. the intrapleural pressure is higher than the intrapulmonary pressure. the lungs expand outward with the chest wall as it expands.

Explanation:

During inflation, air moves in the lungs when the air pressure within the alveolar spaces falls below the atmospheric pressure

The forces that normally cause changes in volume of the chest and lungs arises not only from muscle contraction but from the elastic properties of both the lung and the chest

The force required to maintain inflation of the lung and to cause airflow is provided by the chest and diaphragm (the muscular partition between chest and abdomen), which are in turn stretched inward by the pull of the lungs

Hence during lung inflation, the lungs cling to the internal surface of the chest wall as it expands

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