GYMNOSPERMS - FIRST PLANTS WITH SEEDS
So you've got a vascular system. What comes next? Seeds. Seeds let you send your offspring out into the world.
Gymnosperms
Fossil from the Devonian period reveal fernlike plants that were heterosporous; that is, produced two kinds of spores.
microspores (male) and
megaspores (female).
gymnosperms Flowerless, seed-bearing land plants; the ?rst seed plants; living groups include the pines, ginkgos, and cycads. Naked seeds.
Gymnosperms have seeds but not fruits or flowers. Gymnos means naked, sperm means seed: thus the term gymnosperm = naked seeds.
Gymnosperms
Gyrase
(Date:3/28/2011)... have completed the first human randomized controlled trial ... uses a catheter-based probe inserted into the renal ... nerves near the kidneys (or in the renal ...
Gymnosperms (especially conifers, Bennettitales and cycads) and ferns common. Many types of dinosaurs, such as sauropods, carnosaurs, and stegosaurs. Mammals common but small. First birds and lizards. Ichthyosaurs and plesiosaurs diverse.
The gymnosperms and angiosperms have stems above ground and roots below. The stems can grow thicker and taller each year and therefore they can reach great heights. Both groups have seeds which are dormant embryos released by the parent plant.
Angiosperms evolved from gymnosperms, their closest relatives are Gnetae. Two key adaptations allowed them to displace gymnosperms as the dominant fauna -- fruits and flowers.
woody, usually tall, perennial higher plants (angiosperms, gymnosperms, and some pterophyta) having usually a main stem and numerous branches.
Please contribute to this project, if you have more information about this term feel free to edit this page ...
seed plant Common term for gymnosperms and angiosperms.
seed-scale complex The spirally arranged scales on a female strobilus in gymnosperms.
The female sex organ of liverworts, mosses, ferns, and most gymnosperms. It is usually a flask-shaped organ, comprising a swollen base or venter containing a single egg-cell and a slender elongated neck containing one or more layers of cells.
Examples : Traditionally defined Dinosauria, fish, gymnosperms, invertebrates, protists, etc.
Pollination
Transfer of pollen from the anther to the stigma in angiosperms or from the microsporangium to the micropyle in gymnosperms.
Pollen another name for the male gametophyte in gymnosperms and angiosperms
(pollen = fine flour) ...
Cf. autogamy.
Related Terms:
Pollination
Transfer of pollen from the anther to the stigma in angiosperms or from the microsporangium to the micropyle in gymnosperms.
By the Carboniferous Period, about 355 million years ago, most of the Earth was covered by forests of primitive vascular plants, such as lycopods (scale trees) and gymnosperms (pine trees, ginkgos).
 See also: Plant, Gymnosperm, Species, Organ, Flower
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