The gamete-producing, usually haploid generation in the life cycle of a plant. The gametophyte arises from haploid spores produced as a result of meiosis in the * sporophyte, or diploid, generation. In the bryophytes the gametophyte constitutes a major part of the life cycle and the sporophyte is either partially or totally dependent on it for anchorage and nutrition. In the vascular plants the gametophyte becomes progressively less prominent so that in the angiosperms it is represented by the pollen tube and its nuclei and the embryo sac. In lower plants the gametophyte is unprotected and tends to be highly susceptible to dehydration. It therefore tends to be confined to damp habitats. See also alternation of generations. |
