Breathing pattern of supradiaphragmatic photography

Respiratory movement refers to the rhythmic expansion and contraction of the human chest, including inhalation and exhalation. When inhaling, the intercostal muscles contract and the ribs move upward and outward, which increases the anterior-posterior diameter and left-right diameter of the thorax. At the same time, the diaphragm contracts and the top of the diaphragm drops, which increases the upper and lower diameter of the thorax, increases the volume of the thorax and expands the lungs. The air pressure in the lungs is lower than the outside atmospheric pressure, and the outside air enters the lungs through the respiratory tract to complete inhalation.

Therefore, choose: B.