To aid inhalation, both the diaphragm and intercostal muscles are used. By expanding the thoracic cavity, the action of these muscles creates a space with _____ atmospheric pressure.

Question

Quizplus · Accepted Answer

By expanding the thoracic cavity, the diaphragm and intercostal muscles increase its volume, which leads to a decrease in pressure within the cavity. This decrease in pressure creates a pressure gradient between the thoracic cavity and the outside atmospheric pressure resulting in air being drawn into the lungs. Therefore, the pressure inside the thoracic cavity is lower than the atmospheric pressure.

To Aid Inhalation, Both the Diaphragm and Intercostal Muscles Are