Question

explain the expansion and contraction of the lungs in your own words

Answer 1

When you breathe in, or inhale, your diaphragmcontracts (tightens) and moves downward. This increases the space in your chest cavity, into which your lungs expand. The intercostal muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.

Answer 2

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at the time when air is inhaled by our lungs the diaphragm is a little bit expanded through which the volume of lungs suddenly increased which makes a little vaccum at the bottom of lungs which makes us to inhale some air through our nose and whenever the air is released or exhaled at that time the drive from contract which makes a less volume in the lungs which makes the exhalation of air