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Unformatted text preview: Gymnosperm Adaptations . Gymnosperms are plants that bear seeds that are "naked," meaning not enclosed in an ovary The diploid sporophyte generation is much more highly developed and obvious than the haploid gametophyte generation. A second adaptation of seed plants to dry land was the evolution of pollen, grains are the much-reduced male gametophytes that contain cells that develop into sperm. The third important adaptation is a seed consists of a plant embryo packaged along with a food supply within a protective coat. Female gametophytes develop within structures called ovules . o Within each of two ovules on each scale of the female cones, a large spore cell undergoes meiosis and produces four haploid cells. One of these cells survives and grows into the female gametophyte. Figure 19-13 In pines and other gymnosperms, the gametophytes develop inside cones. Airborne pollen grains (the male In pines and other gymnosperms, the gametophytes develop inside cones....
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- Fall '08