alternation of life phases

  , less correctly alternation of generations. Having distinct sporophytic (diploid), e.g. stems, roots, leaves, cones, etc., and gametophytic (haploid), e.g. tissue within the seeds of cycads and all other seed plants, phases in the life cycle.

Expanded glossary of Cycad terms . 2014.

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  • alternationof generations — alternation of generations n. The regular alternation of forms or of mode of reproduction in the life cycle of an organism, such as the alternation between diploid and haploid phases, or between sexual and asexual reproductive cycles. Also called …   Universalium

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  • Meiosis — Not to be confused with miosis, mitosis, or myositis. For the figure of speech, see meiosis (figure of speech). Events involving meiosis, showing chromosomal crossover Meiosis (pronounced /maɪˈoʊsɨs/&# …   Wikipedia

  • Red algae — Taxobox color = #taxobox color|Plantae name = Red algae image width = 240px domain = Eukaryota unranked phylum = Archaeplastida phylum = Rhodophyta phylum authority = Wettstein, 1922 subdivision ranks = Class subdivision = *Rhodophyceae(There… …   Wikipedia

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