Regarding the assertion and reason; choose the correct option_______
Assertion[A]: The space in your chest cavity increases, into which your lungs expand.
Reason[R]: When the diaphragm tightens and moves downwards, inhalation of air occurs.
Assertion [A] is True and Reason [R] is True but is not a correct explanation to [A].
The diaphragm contracts (tightens) and moves downward. This increases the space in the chest cavity, into which your lungs expand. The intercostal muscles between the ribs also help enlarge the chest cavity. They contract to pull the rib cage both upward and outward when we inhale. This expansion of the lungs creates a vacuum in the lungs that pulls the air in through the nose. The inhalation is the end result and not a part of the process of breathing.