首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
职称考试
DNA Fingerprinting DNA is the genetic material found within the cell nuclei ...
DNA Fingerprinting DNA is the genetic material found within the cell nuclei ...
admin
2020-12-24
32
问题
DNA Fingerprinting
DNA is the genetic material found within the cell nuclei of all living things. In mammals (哺乳动物)the strands of DNA are grouped into structures called chromosomes (染色体) With the exception of identical twins, the complete DNA of each individual is unique.
DNA fingerprinting is sometimes called DNA typing. It is a method of identification that compares bits of DNA. A DNA fingerprint is constructed by first drawing out a DNA sample from body tissue or fluid such as hair, blood, or saliva (唾液)_ The sample is then segmented using enzymes (酶),and the segments are arranged by size. The segments are marked with probes and exposed on X-ray film, where they form a pattern of black bars — the DNA fingerprint. If the DNA fingerprints produced from two different samples match, the two samples probably came from the same person.
DNA fingerprinting was first developed as an identification technique in 1985. Originally used to detect the presence of genetic diseases , it soon came to be used in criminal investigations and legal affairs. The first criminal conviction based on DNA evidence in the United States occurred in 1988. In criminal investigations,DNA fingerprints derived from evidence collected at the crime scene are compared to the DNA fingerprints of suspects, (generally, courts have accepted the reliability of DNA testing and admitted DNA test results into evidence. However, DNA fingerprinting is controversial in a number of areas: the accuracy of the results, the cost of testing, and the possible misuse of the technique.
The accuracy of DNA fingerprinting has been challenged for several reasons. First, because DNA segments rather than complete DNA strands are “fingerprinted” ; a DNA fingerprint may not be unique; large-scale research to confirm the uniqueness of DNA fingerprinting test results has not been conducted. In addition, DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and quality controls. Also, since human beings must interpret the test, human error could lead to false results.
DNA fingerprinting is expensive. Suspects who are unable to provide their own DNA to experts may not be able to successfully defend themselves against charges based on DNA evidence.
Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA fingerprint database.
If two sisters are identical twins,their complete DNAs are_.
选项
A the same
B unique
C different
D similar
答案
A
解析
文本第一段最后一句话提到 “With the exception of identical twins,the complete DNA of each individual is unique”,说明除了双胞胎这个特殊情况外,每个人的完整DNA都是 独一无二的,所以答案是A。
转载请注明原文地址:https://ti.zuoweng.com/ti/6VEQKKKQ
相关试题推荐
Wehavetoactwithintheexistinglegalframework.A:limitB:procedureC:status
Wehavetoactwithintheexistinglegalframework.()A.limitB.procedureC.statu
共用题干 第三篇EatMore,WeighLess,LiveLongerClevergeneticdetectiveworkmayh...
共用题干 第三篇EatMore,WeighLess,LiveLongerClevergeneticdetectiveworkmayh...
共用题干 第三篇EatMore,WeighLess,LiveLongerClevergeneticdetectiveworkmayh...
Wehavetoactwithintheexistinglegalframework.A.limitB.systemC.procedu
34Inthispassage,thethreegeneticallyengineeredmedicalproductsarep...
32GeneticengineeringmaybedefinedasAthealteringofnormalcellreproduc
DNAFingerprinting DNAisthegeneticmaterialfoundwithinthecellnuclei...
DNAFingerprinting DNAisthegeneticmaterialfoundwithinthecellnuclei...
随机试题
持有外汇负债的投资者,为防止未来偿付时该货币升值,可在外汇期货市场做买入套期保值
伴有糖尿病或肾脏病的高血压患者降压目标值为()。 A.135/85mmHg以下
最近一段时间,有关要发生台风的传言很多。一天傍晚,刚刚问在院里乘凉的叔叔:“叔叔
下列关于违反证券交易的法律责任的说法,错误的是()。
证券投资基金反映的是( )关系。
甲、乙、丙、丁4人合伙开了一家新愿零售商店,其中甲出资10万元,乙、丙、丁各出
下列能使心输出量增加的因素是()。 A.心迷走中枢紧张性增高 B.心交感中枢
Doyouthinkyoucandoitbyyourself?
女性,46岁,情绪低落,对周围一切感到兴趣索然。自觉工作太吃力,一切懒于料理,不参加外界活动,整日卧床少动A意志缺乏B意志增强C意志减退D作态E
B企业为金属加工企业,主要从事铝合金轮毂加工制造。 B企业的铝合金轮毂打磨车间为二层建筑,建筑面积2000m2,南北两端各设置载重2.5t的货梯和敞开...