Consider the following scenario. AMU is equivalent to ATOMIC NUMBER. THAT IS, AMU=Z

that's wrong

Explanation:

the AMU(atomic mass unit) is roughly equal to the sum of the number of protons and neutrons in the nucleus.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.