10 What happens when your diaphragm relaxes and moves upward? A Your lungs deflate and you breathe out. B Your lungs inflate and you breathe in. C Your alveoli transfer oxygen to your bloodstream. D Your bloodstream transfers carbon dioxide to your alveoli.
The Correct Answer and Explanation is:
The correct answer is: A. Your lungs deflate and you breathe out.
The diaphragm, a dome-shaped muscle located beneath the lungs, plays a vital role in the breathing process. During inhalation, this muscle contracts and moves downward, expanding the chest cavity and decreasing the pressure inside the lungs. This pressure difference allows air to flow into the lungs.
When the diaphragm relaxes, it moves upward into its dome-shaped position. This upward motion reduces the space in the thoracic cavity, increasing the pressure inside the lungs. As a result, air is pushed out of the lungs, leading to exhalation. This process does not actively involve pulling air out but rather relies on the natural elasticity of the lungs and chest wall to expel air.
Exhalation primarily serves to remove carbon dioxide, a waste product of cellular metabolism. While oxygen is vital for energy production, carbon dioxide must be expelled to maintain proper blood pH and prevent respiratory acidosis. The upward movement of the diaphragm assists in efficiently clearing this gas from the body.
Alveoli, the tiny air sacs in the lungs, facilitate the exchange of gases during breathing. However, their primary function occurs during inhalation, where oxygen passes into the bloodstream, and carbon dioxide exits into the alveoli for removal. This exchange continues as long as breathing occurs but is not directly caused by the diaphragm relaxing.
The entire respiratory process operates automatically under the control of the brainstem, ensuring that oxygen delivery and carbon dioxide removal occur seamlessly. The relaxation of the diaphragm and the subsequent exhalation highlight the importance of muscle coordination in sustaining life and maintaining internal balance.
