Fern

Marattiopsida

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Osmundopsida

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Gleicheniopsida

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Pteridopsida

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A fern, or pteridophyte, is any one of a group of some twenty thousand species of plants classified in the Division Pteridophyta, formerly known as Filicophyta. A fern is defined as a vascular plant that does not produce seeds, but reproduces by spores to initiate an alternation of generations. New sporophyte fronds typically arise by circinate vernation (that is, "leaf" formation by unrolling).

Related Topics:
Plant - Vascular plant - Seed - Spore - Alternation of generations - Circinate vernation

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