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The similar structure is the product of convergent evolution. Beyond those superficial resemblances, there are a number of differences between cycads and palms. For one, both male and female cycads are gymnosperms and bear cones (strobili), while palms are angiosperms and so flower and bear fruit.
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 ...
The spermatophytes were traditionally divided into angiosperms, or flowering plants, and gymnosperms, which includes the gnetophytes, cycads, [5] ginkgo, and conifers. Older morphological studies believed in a close relationship between the gnetophytes and the angiosperms, [ 6 ] in particular based on vessel elements .
Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, flowers , which are the reproductive structures of angiosperms , are the most varied physically and show a correspondingly great diversity ...
In cycads, however, various enzymes have been identified in the pollen tube that direct growth and the nucellus tissues are more damaged with the tube growth. [ 18 ] In other phyla of gymnosperms, the Coniferophyta and Gnetophyta , the sperm is non motile, and the pollen tube delivers the sperm to the egg directly, in a process called siphonogamy .
These cells cannot swim backwards due to the nature of their propulsion. The uniflagellated sperm cells (with one flagellum) of animals are referred to as spermatozoa, and are known to vary in size. [citation needed] Motile sperm are also produced by many protists and the gametophytes of bryophytes, ferns and some gymnosperms such as cycads and ...
While there are more than 200 species of cycads, only one is native to Florida, and only a couple are popular landscaping plants in our area.
Plant anatomy or phytotomy is the general term for the study of the internal structure of plants.Originally, it included plant morphology, the description of the physical form and external structure of plants, but since the mid-20th century, plant anatomy has been considered a separate field referring only to internal plant structure.