2016届高考英语二轮复习阅读理解一百四十集选练：（18）_高考复习指南

2016届高考英语二轮复习阅读理解一百四十集选练：（18）

　　Genetic（基因的）engineering is the scientific change of the genetic material in a living organism． It allows scientists to identify specific genes, to remove them from an organism's chromosomes （染色体）, improve them, analyze them, and possibly clone them, and to then reinsert the changed gene into the original organism, or a completely different organism．Unlike traditional breeding （繁殖）, where a desired quality would be bred within the same species,

　　genetic engineering can insert desired ones into organisms of different species．Wow--Did you catch that?

　　Genetic engineering creates many positive contributions to agriculture． For example, by genetically engineered（GE） foods,

　　anti-cancer agents,

　　minerals and vitamins can be increased．Improved taste,

　　shelf life, and better transport are all possible．Also, GE plants can increase pest and bacterial resistance, therefore, making the food safe for consumers．

　　But some argue that the possible negative effects outweigh the positives, and critics are starting to voice their concerns．

　　Unlike Europe, in the United States labeling is not required on genetically engineered foods or on foods that contain genetically engineered products． Most Americans do not realize that they are, in fact, eating GE foods．

　　The public is also concerned about the unknown health risks．With limited understanding of genes, scientists cannot predict possible effects．Because most genes introduced into GE plants come from sources not introduced into the human body,