Mitochondria are critical for life, converting food and oxygen into ATP, and their function stopping leads to rapid death.

“so these tiny little organel and the PowerHouse of the cell reference means that mitochondria take the breakdown products of the food that we're eating they are the primary thing using the oxygen that we're breathing in they are creating the carbon dioxide that we're breathing out and that they are turning food into ATP which is the energy currency of the cell so they're taking food and oxygen and lots of other things but let's just simplify food and oxygen converting it into ATP and that is what the PowerHouse of the cell kind of refers to there is no doubt they do that there is no doubt that when that process stops humans have about six minutes or so and then we're dead that process is critical to life there is no other process in the body that you can disrupt that will kill the organism faster it is Central to living organisms this production of ATP”