英国诺丁汉特伦特大学植物学Essay代写:什么是裸子植物

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裸子植物是无花植物,可产生锥体和种子。术语裸子植物字面意思是“裸种子”,因为裸子植物种子不包裹在卵巢内。相反,它们暴露在称为苞片的叶状结构的表面上。裸子植物是浮萍植物的维管植物,包括针叶树,苏铁,银杏和gnetophytes。这些木本灌木和树木中一些最容易识别的例子包括松树,云杉,冷杉和银杏。裸子植物在温带森林和北方森林生物群落中很多,其物种可以忍受潮湿或干燥的条件。与被子植物不同,裸子植物不会产生花朵或果实。它们被认为是第一批居住在三叠纪时期的土地上的第一批维管植物,大约在245-208万年前。能够在整个植物中输送水的血管系统的发展使得裸子植物的土地定植成为可能。今天,有超过一千种裸子植物属于四个主要部门:Coniferophyta,Cycadophyta,Ginkgophyta和Gnetophyta。

英国诺丁汉特伦特大学植物学Essay代写:什么是裸子植物

Gymnosperms are flowerless plants that produce cones and seeds. The term gymnosperm literally means “naked seed,” as gymnosperm seeds are not encased within an ovary. Rather, they sit exposed on the surface of leaf-like structures called bracts. Gymnosperms are vascular plants of the subkingdom Embyophyta and include conifers, cycads, ginkgoes, and gnetophytes. Some of the most recognizable examples of these woody shrubs and trees include pines, spruces, firs, and ginkgoes. Gymnosperms are abundant in temperate forest and boreal forest biomes with species that can tolerate moist or dry conditions. Unlike angiosperms, gymnosperms do not produce flowers or fruit. They are believed to be the first vascular plants to inhabit land appearing in the Triassic Period around 245-208 million years ago. The development of a vascular system capable of transporting water throughout the plant enabled gymnosperm land colonization. Today, there over one thousand species of gymnosperms belonging to four main divisions: Coniferophyta, Cycadophyta, Ginkgophyta, and Gnetophyta.

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