Fig. 3
From: Emergence of life: Physical chemistry changes the paradigm
Left: Escherichia coli cells as rods about 1000 nm in diameter and 3000 nm long. Right: computer simulation of crowding in an E. coli cell; proteins/RNA occupy ~25 % of cell volume; if not in complexes, proteins are on average about 1–2 nm apart. There are about 4 × 106 proteins/cell, 20 × 109 H2O/cell, and 12 × 107 ions/cell, mostly K+, corresponding to ionic strength of about 0.25 M