Relative standard deviations of plastome measures.

In contrast to plastids, the size of the plant chondriome (Fig. 2) increased from algae to angiosperms, with lower variance in algae than in angiosperms (Table 4). For angiosperms, the variance was higher in the number of protein-coding genes than for nonvascular land plants and algae. The coding region of the chondriome decreased from 52% in algae to 15% in angiosperms, but the variance remained similar. However, the number of proteins coded by the chondriome increased with an increasing variance. The number of structural RNAs of the mitochondria remained similar in all species. The amount of noncoding DNA increased in all three cellular organelles (nucleus, plastid, and mitochondria), but the size of coding DNA increased concurrently only in the nucleus (data not shown). Relative standard deviations of plastome measures.