Question

Is there any system in our body where pressure is built up?

Answer 1

Part1: Pressure
At a fixed temperature, the pressure of a system is inversely proportional to volume.

Part 2: Pressure build up in respiratory system during exhalation

During the process of breathing, our pulmonary volume is controlled by the thoracic volume.
During inhalation, the volume of the thoracic cavity increases (due to downward movement of the diaphragm and expansion of the ribcage) thereby increasing the pulmonary volume. This in turn decreases the pressure inside our lungs. Therefore, the air rushes from the higher pressure (atmospheric pressure) to lower pressure (inside our lungs).

During exhalation, the pressure inside our lungs builds up because the pulmonary volume decreases. This is due to upward movement of the diaphragm and restoration of the size of the ribcage, thereby reducing the size of the thoracic cavity. The increased pressure build-up in lungs results in exhalation of the air from higher pressure (inside the lungs) to lower pressure (atmosphere).

Part 3:Pressure build up in circulatory system
Heart helps in the transportation of blood throughout the body. With each pump generated by the heart, blood is pumped with higher pressure away from the heart through blood vessels. The pressure exerted by the blood on the walls of the artery helps in transporting this blood to various organs.