绿色植物在生命活动中依靠什么来建造自己的细胞和组织呢?据分析,构成植物体的元素约有60余种,其中含量最多的碳、氢、氧(占植物鲜重的98％以上),主要是来自空气和水,并通过光合作用固定下来。这些元素,最初都是地球岩石的成分,所以称为矿质元素。氮素虽不存在于土壤母质中,但因植物对氮素的吸收方式与吸收矿质元素相似,所以它也被看 According to the analysis, there are about 60 kinds of elements that constitute plants, of which carbon, hydrogen and oxygen are the most abundant (accounting for more than 98% of fresh weight of plants) , Mainly from air and water, and fixed by photosynthesis. These elements, originally composed of the Earth’s rock, are called mineral elements. Although nitrogen is not present in the soil parent material, it is also seen because plants absorb nitrogen in a manner similar to that of mineral elements