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14 Οκτ 2024 · Gymnosperm, any vascular plant that reproduces by means of an exposed seed, or ovule—unlike angiosperms, or flowering plants, whose seeds are enclosed by mature ovaries, or fruits. The seeds of many gymnosperms (literally ‘naked seeds’) are borne in cones and are not visible until maturity.
The gymnosperms and angiosperms together constitute the spermatophytes or seed plants. The spermatophytes are subdivided into five divisions, the angiosperms and four divisions of gymnosperms: the Cycadophyta, Ginkgophyta, Gnetophyta, and Pinophyta (also known as Coniferophyta). Newer classification place the gnetophytes among the conifers. [3]
Gymnosperms are classified into four types as given below – Cycadophyta. Cycads are dioecious (meaning: individual plants are either all male or female). Cycads are seed-bearing plants where the majority of the members are now extinct. They had flourished during the Jurassic and late Triassic era.
3 Αυγ 2023 · Definition: Gymnosperms are the plants that are most ancient vascular, flowerless, seed-producing, and can reproduce through an exposed seed or ovule. They produce seeds without fruits which means the ovules and the seeds that develop from these ovules are not enclosed in the fruit wall.
26 Οκτ 2024 · Gymnosperms are one of the oldest groups of seed-producing plants, predating the flowering plants known as angiosperms. They are integral to many ecosystems, providing habitat, food, and resources for a variety of organisms. Their resilience and ability to adapt to diverse environments make them a critical component of the plant kingdom, particularly in cooler climates and higher altitudes.
8 Οκτ 2024 · The gymnosperms are classified into four primary divisions: Coniferophyta, Cycadophyta, Ginkgophyta, and Gnetophyta. Each division encompasses distinct plant groups, contributing to the overall diversity of gymnosperms.
1 Ιουλ 2022 · Here, we review major advances of gymnosperm phylogeny over the past 10 years and propose an updated classification of extant gymnosperms. This new classification includes three classes (Cycadopsida, Ginkgoopsida, and Pinopsida), five subclasses (Cycadidae, Ginkgoidae, Cupressidae, Pinidae, and Gnetidae), eight orders (Cycadales, Ginkgoales ...
