Answer:
Itβs so fragile even just saying its name can break it. What is it?
What is the ending of all that begins?
There's one in every deck of cards and in a famous movie
The distance from the top of your head to the floor standing up straight.
Turns us on our backs, and open up our stomachs. You will be the wisest of men though at start a lummox.
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.