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| | Brooklyn Botanic Garden: GARDEN BOTANY |
 | | Gymnosperms are plants with vascular tissue and are considered more advanced than both bryophytes and ferns because, among other things, they produce seeds. |
 | | Gymnosperms are woody and may be trees, shrubs, or even vines. |
 | | In addition, all gymnosperms are heterosporous, meaning that they produce two types of spores, small male spores called microspores and large female spores called megaspores -- a condition also true of certain ferns, Selaginella (the spike mosses), Isoetes (the quillworts), and all flowering plants. |
| www.bbg.org /gar2/topics/botany/repro_gymnosperms.html (1024 words) |
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