For much of human history, animals and plants were perceived to follow a different set of rules than the rest of the universe. In the 18th and 19th centuries, this culminated in a belief that living organisms were infused by a non-physical energy or “life force” that allowed them to perform remarkable transformations that couldn’t be explained by conventional chemistry or physics alone.
Scientists now understand that these transformations are powered by enzymes — protein molecules comprised of chains of amino acids that act to speed up, or catalyze, the conversion of one kind of molecule (substrates) into another (products). In so doing, they enable reactions such as digestion and fermentation — and all of the chemical events that happen in every one of our cells — that, left alone, would happen extraordinarily slowly.
“A chemical reaction that would take longer than the lifetime…
