 In mosses and liverworts, the gametophyte is relatively large, and the sporophyte is a much smaller structure that is never separated from the gametophyte.In ferns, gymnosperms, and flowering plants (angiosperms), the gametophytes are relatively small and the sporophyte is much larger.In gymnosperms and flowering plants the megagametophyte is contained within the ovule (that may develop into a seed) and the micro gametophyte is contained within a pollen grain.