Figure 3.

Images of model bare-regions comprising (left) triangular profile filaments on a hexagonal lattice and (right) their diffraction patterns. (a) Single orientation filaments as seen in bony fish muscle. (b) Perfect superlattice formed by relative rotations of 0, 40° and 80° between adjacent filaments. (c) Bare-region model for frog muscle with only two orientations, 0 and 180° (or 60°) apart as observed in electron micrographs and constructed using the no-three-alike rules. The randomness in (c) leads to noise in the diffraction pattern in the right panel compared with the ordered noise-free patterns in (a) and (b). Adapted from [18], with permission from Elsevier.