2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、Full Terms improving thetaste, flavor, appearance, and other desirable items; and enhancement of storage time.? Resistance to microorganisms and pests. ? Enhancing and protecting the yield.? Operating under severe condi

2、tions. ? Enhancing other key properties.The evolution of agricultural development can bereasonably described in three phases consisting of selection of useful but naturally occurring plants, cross- breeding of existing p

3、lants, and using science and tech-nology to produce the most desirable plants.Phase IDuring the first phase, the farmers attempted to findand select the most efficient plants and use them. Thisselection was primarily bas

4、ed on the availability of aplant at a specific location. The evolution of this phasewas described by Wieczorek and Wright [6], includinghow farmers attempted to select plants based on anumber of relevant parameters. This

5、 phase known assedentary agriculture dates back 9000 years. Forexample, archeological studies by Piperno et al. [7]found that ancient grains and tools used by civilizationsdated back 8700 years. Their studies found that

6、the ear-liest farmers chose food plants that had desirable char-acteristics and expanded on those plants. Note that asdescribed by Davis et al. [8], the nutritional content ofthe various crops changes naturally.Phase IIT

7、he second phase emerged when the agricultural com-munity recognized the limitations of naturally occurringcrops. Although cross breeding had been known forcenturies, scientific understanding of the process pro-vided uniq

8、ue opportunities for the development andapplication of cross-breeding to improve agriculturalproduction. This phase started when Mendel [9], oftenreferred to as the father of modern genetics, providedthe scientific found

9、ation for cross-breeding in 1866.Mendel studied pea plant hybridization and establishedthe law of inheritance. The primary objective of cross-breeding is to identify two plants, each having a desir-able feature and cross

10、-breed them to produce a plantthat has both desirable features. Shull [10–12] describedthe genetic changes in specific plants as a consequenceof cross breeding. Following the spread of Mendel’swork, many researchers took

11、 it upon themselves to fur-ther research this area with the objective of improvingcrop production in both quality and quantity.Phase IIIThe third phase consists of GE crops, one of the keyprocesses within the GMO, a proc

12、ess extensively usedto develop crops by expanding the processes used inthe second phase and genetically modifying the struc-ture of the plant. The process used by the FDA in regu-lating GMO is best described in their sta

13、tement “Foodfrom GE plants must meet the same food safety require-ments as food derived from traditionally bred plants”.Since the 1990s, scientific advancement has allowed fora more specific method of GMO, known as gene

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