Photosynthesis occurs within the plant's photosynthetic reaction center. The curled ribbons are the main pieces of the protein. Chlorophyll molecules are shown in green, dark green, and turquoise. The magenta molecules are pheophytins, which are similar to chlorophylls except a magnesium ion is replaced by two proteins. In red are two quinones. Even with approximations, Wheeler's simulations track 4,500 atoms in these molecules. (Adapted from the X-ray diffraction structure of Ermler et al. "Structure" 2:925-936, 1994.)
