There appears to be a set of permitted parameters available to the plant, and plant structures are limited by this set of parameters. Gravity is an important influence on this set of parameters. This set of parameters includes a set of permitted frequencies which determine internodal spacings and cell dimensions. We cannot go into all details of plant structure here but W-waves determine much of how plants, and likely all life, develop. In our study of plant internodal spacings it appears that these are permitted to have only certain discrete values determined by allowed frequencies and growth angles ( growth angles determine wave velocity). (see the Wagner paper A Basis for A Unified Theory for Plant Growth and Development). Recently we have found that growth angles are also quantized. It is almost like there is a template out there and plant structures (including cell structure) are constrained by the limits provided by that template. In the microgravity environment of space the gravity feature is missing and cells, for example, may grow in an odd shaped fashion (see Halstead et. al. Plants in Space in Annual Reviews of Plant Physiology volume 38 pages 317-345 (1987). See Waves in Dark Matter for more details.