植物

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植物(plant)

植物界中所有生物的统称，由多细胞、真核的生命形式组成（参阅eucaryote），六项基本特徵为︰几乎均通过光合作用取得营养；分生组织能无限制的生长；细胞壁含纤维素，因此多少较为坚韧；缺乏运动器官；缺乏感觉器官和神经系统；生活史中显现世代交替。没有一个定义能完全排除所有非植物的生物体或包含所有的植物。例如，许多植物并非绿色，不能进行光合作用自制养料，而是寄生於其他活的植物体上（参阅parasitism），另一些则从死亡的生物体获取营养。许多动物具类似植物的特徵，例如缺乏移动能力（如海绵）或生长方式类似植物（如某些珊瑚和苔藓动物），但一般来说这些动物缺少上述的其他植物特徵。过去的一些分类系统（参阅taxonomy），将一些难归类的类群，如原生动物、细菌、藻类、黏菌和真菌（参阅fungus）归入植物界，但这些生物体在形态上和生理上与植物有很大的不同，这使大部分科学家将它们画出植物界。

English version：

plant

Any organism in the kingdom Plantae, consisting of multicellular, eukaryotic life forms (see eukaryote) with six fundamental characteristics: photosynthesis as the almost exclusive mode of nutrition, essentially unlimited growth at meristems, cells that contain cellulose in their walls and are therefore somewhat rigid, the absence of organs of movement, the absence of sensory and nervous systems, and life histories that show alternation of generations. No definition of the kingdom completely excludes all nonplant organisms or even includes all plants. Many plants, for example, are not green and thus do not produce their own food by photosynthesis, being instead parasitic on other living plants (see parasitism). Others obtain their food from dead organic matter. Many animals possess plantlike characteristics, such as a lack of mobility (e.g., sponges) or the presence of a plantlike growth form (e.g., some corals and bryozoans), but in general such animals lack other plant characteristics. Some past classification systems (see taxonomy) placed difficult groups such as protozoans, bacteria, algae, slime molds, and fungi (see fungus) in the plant kingdom, but structural and functional differences between these organisms and plants have convinced most scientists to classify them elsewhere.

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