Several Nobel prizes in Physiology or Medicine were awarded for helping us understand what makes our cells alive and functioning as they should.
The atoms from which we are built were created by the action of stars billions of years in the past. Many of those atoms have now temporarily organized to take on human form. After our death, they will disorganize again and return to nature. This realization leaves us with the question — what makes the difference between living and non-living at all? Clearly, the same atoms can be incorporated into living and non-living matter at different times.