It’s a familiar image, reprinted in countless biology textbooks: an illustration of a typical cell, halved like a grapefruit to reveal its innards. Strands of endoplasmic reticulum encircle a nucleus that floats in the center like a raft. RNA molecules wait patiently at ribosomes to deliver recipes for making proteins. A few vacuoles and Golgi bodies bob about. A mostly deserted cytosol offers a…