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澳洲留学生作业代写:细菌物种的能力

近年来,一些细菌物种表现出了非凡的能力,能够对某些类型的抗生素产生耐药性,这些抗生素通常用于治疗最常见的疾病。抗生素是指真菌或细菌为争夺有限的资源而释放出的一种自然物质或物质,用以杀死相互竞争的微生物。最近,科学家们发现,一些菌株已经开始通过不同的突变或生物遗传物质(DNA)的改变对某些抗生素产生耐药性。这种耐药性导致细菌分子物质发生变化,主要是由于抗生素过量或不足、卫生条件差和环境变化等事件。如果目标细菌的编码特定蛋白的基因的分子物质发生了变化,那么抗生素就不能与受影响的蛋白结合,因此突变的细菌有机体得以存活(Purdom, 2007)。在抗生素的作用下,发生自然选择的过程,从而有利于突变或畸形细菌的生长、发育、繁殖和生存。当细菌从其他微生物那里获得突变的遗传物质时,自然选择的概念也发挥了作用。这就允许DNA转移到细菌中,从而改变细菌的结构,使其向后代转移新的DNA。新DNA的存在使下一代对抗生素产生抗药性。自然选择和突变的概念支持细菌种群对抗生素产生耐药性。另一方面,这些通过自然选择发生的变化也导致了具有缺陷蛋白的菌株的出现,这些缺陷蛋白往往具有不正常的功能。

澳洲留学生作业代写:细菌物种的能力

In recent past, some bacteria species have showed extraordinary ability to develop resistance to certain type’s antibiotics, which are commonly used to treat most common illnesses. An antibiotic refers to a natural matter or material that is released by fungi or bacteria to kill competing micro – organisms for limited available resources. In recent past scientists have discovered that some bacteria strains have started showing resistance to certain antibiotics through different mutations, or alterations in the organisms genetic material (DNA).This resistance results in situation where changes occur in the bacteria molecular material and mostly results from events such as antibiotic over and under prescription, poor hygiene, and environmental changes. If the target bacteria obtain changes in its molecular material for genes coding a specific protein, the antibiotic then cannot bind to affected protein hence the mutant bacterial organism survive (Purdom, 2007). Under the effects of antibiotics, the process of Natural Selection occurs, thus favoring the growth, development, reproduction, and survival and of the mutant or malformed bacteria.Concept of natural selection also plays part when bacteria obtain mutated genetic material from other micro – organisms, where they swap genetic material from each other. This allows transfer of DNA into the bacteria, thus altering its structure making them transfer new DNA to its offsprings.Presence of new DNA makes the next generation resistant to antibiotic. The concept of natural selection and mutation supports bacteria populations to become resistant to antibiotics. On the other hand, these changes through natural selection also lead to emergence of strains with defective proteins that tend to have abnormal functions.

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