论文部分内容阅读
包括人工合成的在内,现在我们的星球上存在着107种元素。由于生命过程无时不在与围周环境进行着相互作用,几乎所有的元素都可以进入生物体中。存在于生物体内的元素常被分为四类:①必需元素;②有益元素;③沾污元素;④有毒元素。其中人们最为关心的是必需元素。关于生命元素的必需性,最为普遍接受的是阿农提出的标准:①完全缺乏该元素,生物不能正常生长和繁殖;②该元素在生物体内的作用不能被另一种元素完全代替;③它对生物功能的作用是直接的,并参与代谢过程。必需元素按其在生物体内含量的不同,
Including synthetic, there are now 107 elements on our planet. As life processes interact with the peri-environment all the time, almost all elements can enter the organism. The elements present in the body are often divided into four categories: ① essential elements; ② beneficial elements; ③ stain elements; ④ toxic elements. One of the most concerned about is the necessary element. The most commonly accepted criterion for the necessity of life elements is the standard proposed by Aghan: ① the complete lack of the element, the inability of the organism to grow and reproduce normally; ② the element’s in vivo function can not be completely replaced by another element; ③ it The role of biological function is direct and involved in the metabolic process. Essential elements according to their content in different organisms,