Carpels are thought to be phylogenetically derived from ovule-bearing leaves or leaf homologues ( megasporophylls ), which evolved to form a closed structure containing the ovules.
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This species is distinguished by its narrow, glabrous leaflets with strongly recurved margins; its long, slender microsporangiate cones; and its long megasporophylls with long, sterile apices.
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A carpel has a similar function to a megasporophyll, but typically includes a stigma, and is fused, with ovules enclosed in the enlarged lower portion, the ovary.
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Pollen-producing cones fusiform ( tapering at both ends ), Megasporophylls ( female, ovule-producing ) up to 30 cm long, each with 2-5 ovules.
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The " female " cells called megaspores, which will divide to become the egg cell ( megagametogenesis ), are contained in the ovule and enclosed in the carpel ( or megasporophyll ).
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The pollen grains are dispersed by the wind to the female, ovulate cone that is made up of many overlapping scales ( sporophylls, and thus megasporophylls ), each protecting two ovules, each of which consists of a megasporangium ( the nucellus ) wrapped in two layers of tissue, the integument and the cupule, that were derived from highly modified branches of ancestral gymnosperms.