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The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers.They differ from mosses by being vascular, i.e., having specialized tissues that conduct water and nutrients, and in having life cycles in which the branched sporophyte is the dominant phase.
The Pteridophyte Phylogeny Group (PPG) is an informal international group of systematic botanists who collaborate to establish on the classification of pteridophytes (lycophytes and ferns) that reflects knowledge about plant relationships discovered through phylogenetic studies. In 2016, the group published a classification for extant ...
The gymnosperms (/ ˈ dʒ ɪ m n ə ˌ s p ɜːr m z,-n oʊ-/ ⓘ nə-spurmz, -noh-; lit. ' revealed seeds ') are a group of woody, perennial seed-producing plants, typically lacking the protective outer covering which surrounds the seeds in flowering plants, that include conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae [2] The term gymnosperm comes from the ...
Proponents of this theory point out that the gymnosperms have two very similar copies of the gene LFY while angiosperms only have one. Molecular clock analysis has shown that the other LFY paralog was lost in angiosperms around the same time as flower fossils become abundant, suggesting that this event might have led to floral evolution. [ 71 ]
The fossil history of flowering plants records the development of flowers and other distinctive structures of the angiosperms, now the dominant group of plants on land.The history is controversial as flowering plants appear in great diversity in the Cretaceous, with scanty and debatable records before that, creating a puzzle for evolutionary biologists that Charles Darwin named an "abominable ...
2] [3] [4] They are regarded as seed ferns because they are seed-bearing plants with fern-like leaves. [4] Although at one time considered angiosperms because of their berry-like cupules, [5] that hypothesis was later disproven. [6] Nevertheless, some authorities consider them likely ancestors or close relatives of angiosperms. [7]
Glossopteris (etymology: from Ancient Greek γλῶσσα (glôssa, " tongue ") + πτερίς (pterís, " fern ")) is the largest and best-known genus of the extinct Permian order of seed plants known as Glossopteridales (also known as Arberiales, Ottokariales, or Dictyopteridiales).
The remainder of the vascular plant sections address the higher plants (spermatophytes or seed plants, i.e. gymnosperms and angiosperms or flowering plants). In the higher plants, the terrestrial sporophyte has evolved specialised parts. In essence, they have a lower, underground component and an upper, aerial component.