I've mentioned here before Ursula Goodenough's little book The Sacred Depths of Nature, a lovely reflection on religious naturalism. But it's more than that. Strip out the religious meditations and you have the shortest, clearest introduction to biochemistry you'll ever want or need.
In two pages, for instance, she explains the workings of enzymes, those long strings of amino acids that curl into curious shapes like the pieces of a three-dimensional jigsaw puzzle. The "pockets" in the outer surface of an enzyme attract other molecules that fit into the cavities like keys into locks. Pockets filled, the enzyme twists and brings small molecules together to form large ones, or wrenches large molecules apart. The products are expelled and the enzyme resumes its original shape, waiting to do its work again.
"And that's basically all there is to biochemistry," writes Goodenough.
Talk about understatement!
As I sit here writing, in every one of the trillions of cells in my body thousands of different kinds of enzymes are twisting and turning, building and deconstructing, catalyzing the biochemistry that keeps me alive. Yes, I guess that's basically all there is -- all (in E. E. Cummings' words) "which is natural which is infinite which is yes."