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A conifer cone, or in formal botanical usage a strobilus, pl.: strobili, is a seed-bearing organ on gymnosperm plants, especially in conifers and cycads. They are usually woody and variously conic, cylindrical, ovoid, to globular, and have scales and bracts arranged around a central axis, but can be fleshy and berry-like.
In conifers, the reproductive structures are borne on cones. The cones are either pollen cones (male) or ovulate cones (female), but some species are monoecious and others dioecious . A pollen cone contains hundreds of microsporangia carried on (or borne on) reproductive structures called sporophylls.
To fertilize the ovum, the male cone releases pollen that is carried in the wind to the female cone. This is pollination. (Male and female cones usually occur on the same plant.) The pollen fertilizes the female gamete (located in the female cone). Fertilization in some species does not occur until 15 months after pollination. [23]
Pollen itself is not the male gamete. [4] It is a gametophyte, something that could be considered an entire organism, which then produces the male gamete.Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive) cell.
A type of fruit, usually woody, ovoid to globular, including scales, bract s, or bracteoles arranged around a central axis, e.g. in gymnosperms, especially conifers and Casuarina. conflorescence A rarely used term describing substantial differences between the overall structure of an inflorescence and that of its individual branches, e.g. the ...
For one, both male and female cycads are gymnosperms and bear cones (strobili), while palms are angiosperms and so flower and bear fruit. The mature foliage looks very similar between both groups, but the young emerging leaves of a cycad resemble a fiddlehead fern before they unfold and take their place in the rosette, while the leaves of palms ...
Gnetophyta (/ n ɛ ˈ t ɒ f ɪ t ə, ˈ n ɛ t oʊ f aɪ t ə /) is a division of plants (alternatively considered the subclass Gnetidae or order Gnetales), grouped within the gymnosperms (which also includes conifers, cycads, and ginkgos), that consists of some 70 species across the three relict genera: Gnetum (family Gnetaceae), Welwitschia (family Welwitschiaceae), and Ephedra (family ...
The pollen cones are cylinder-shaped with a yellow, brownish color, and are up to 1.8 inches long. Seed cones need two years to mature after pollination. In some cases, they will drop their seeds, but in most Pinus serotina, they will persist and hold their seeds. The color of the seed cones and seed scales is red-brown in color.