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
12
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/ObEQKKKQ
相关试题推荐
Thejournalistiscollectingmaterialforanarticle.A:data B:fabric C:substan
Thechefsinthisrestaurantinsistonhighstandardsofmaterials.A:dependon
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
32GeneticengineeringmaybedefinedasAthealteringofnormalcellreproduc
DNAFingerprinting DNAisthegeneticmaterialfoundwithinthecellnuclei...
随机试题
根据系统安全理论,下列关于系统中危险源控制的观点,正确的是()。 A.不可能消
依法取得的房屋所有权连同该房屋占用范围内的土地使用权,可以设定抵押权,但前提条件
商业银行理财业务经营部门应当组建专业的理财产品投资研究团队,研究( )等发展情况
关于银屑病正确的是 A.欧美发病率低于我国 B.有传染性 C.四肢屈侧多见
正常幼儿每日总热量的需求为每千克体重( )千焦耳,而且各种供能营养素之间应保持
SS3型电力机车在各牵引电机支路中分别接入有__________,这是为了让各支路在机车惰力运行时不构成并联支路、形成环流。
推行临床科学合理用血的最主要目的是A.减少临床用血量B.降低患者医疗费用C.保护血液资源D.減轻采供血机构压力E.避免输血风险
除用于局麻外,亦用于治疗心律失常的药物是( )A.利卡多因B.可待因C.丁卡因D.普鲁卡因E.咖啡因
属于药品标准的是()。A.《国家食品药品监督管理局标准》B.《中药大辞典》C.《中药材》D.《神农本草经》E.《中华本草》
下列统计变量中,属于定量变量的是()。A.性别B.年龄C.产品等级D.汽车品牌