精品一区二区中文在线,无遮挡h肉动漫在线观看,国产99视频精品免视看9,成全免费高清大全

英語(yǔ)四級(jí)考試閱讀復(fù)習(xí)指導(dǎo)

時(shí)間:2024-10-11 19:47:08 學(xué)人智庫(kù) 我要投稿
  • 相關(guān)推薦

英語(yǔ)四級(jí)考試閱讀復(fù)習(xí)指導(dǎo)

  形成天才的決定因素應(yīng)該是勤奮。下面是CN人才網(wǎng)為大家整理的2017年英語(yǔ)四級(jí)考試閱讀復(fù)習(xí)指導(dǎo),歡迎參考~

英語(yǔ)四級(jí)考試閱讀復(fù)習(xí)指導(dǎo)

  2017年英語(yǔ)四級(jí)考試閱讀復(fù)習(xí)指導(dǎo)

  A controversy erupted in the scientific community in early 1998 over the use of DNA (deoxyribonucleic acid ) fingerprinting in criminal investigations. DNA fingerprinting was introduced in 1987 as a method to identify individuals based on a pattern seen in their DNA, the molecule of which genes are made. DNA is present in every cell of the body except red blood cells. DNA fingerprinting has been used successfully in various ways, such as to determine paternity where it is not clear who the father of a particular child is. However, it is in the area of criminal investigations that DNA fingerprinting has potentially powerful and controversial uses.

  DNA fingerprinting and other DNA analysis techniques have revolutionized criminal investigations by giving investigators powerful new tools in the attempt to trove guilt, not just establish innocence. When used in criminal investigations, a DNA fingerprint pattern from a suspect is compared with a DNA fingerprint pattern obtained from such material as hairs or blood found at the scene of a crime. A match between the two DNA samples can be used as evidence to convict a suspect.

  The controversy in 1998 stemmed form a report published in December 1991 by population geneticists Richard C. Lewontin of Harvard University in Cambridge, Mass., and Daniel L. Hartl called into question the methods to calculate how likely it is that a match between two DNA fingerprints might occur by chance alone. In particular, they argued that the current method cannot properly determine the likelihood that two DNA samples will match because they came from the same individual rather than simply from two different individuals who are members of the same ethnic group. Lewontin and Hartl called for better surveys of DNA patterns methods are adequate.

  In response to their criticisms, population geneticists Ranajit Chakraborty of the University of Texas in Dallas and Kenneth K.Kidd of Yale University in New Haven, Conn., argued that enough data are already available to show that the methods currently being used are adequate. In January 1998, however, the federal Bureau of Investigation and laboratories that conduct DNA tests announced that they would collect additional DNA samples form various ethnic groups in an attempt to resolve some of these questions. And, in April, a

  National Academy of Sciences called for strict standards and system of accreditation for DNA testing laboratories.

  1. Before DNA fingerprinting is used, suspects____.

  A.would have to leave their fingerprints for further investigations

  B.would have to submit evidence for their innocence

  C.could easily escape conviction of guilt

  D.cold be convicted of guilt as well

  2. DNA fingerprinting can be unreliable when ____.

  A.the methods used for blood- cell calculation are not accurate

  B.two different individuals of the same ethnic group may have the same DNA fingerprinting pattern

  C.a match is by chance left with fingerprints that happen to belong to two different individuals

  D.two different individuals leave two DNA samples.

  3. To geneticists like Lewontin and Hartl, the current method ____.

  A.is not so convincing as to exclude the likelihood that two DNA samples can never come from two individuals

  B.is arguable because two individuals of the same ethnic group are likely to have the same DNA pattern.

  C.Is not based on adequate scientific theory of genetics

  D.Is theoretically contradictory to what they have been studying

  4. The attitude of the Federal Bereau of Investigation shows that ____.

  A.enough data are yet to be collected form various ethnic groups to confirm the unlikelihood of two DNA samples coming from two individual members

  B.enough data of DNA samples should be collected to confirm that only DNA samples form the same person can match

  C.enough data are yet to be collected from various ethnic groups to determine the likelihood of two different DNA samples coming form the same person

  D.additional samples from various ethnic groups should be collected to determine that two DNA samples are unlikely to come from the same person

  5. .National Academy of Sciences holds the stance that ____.

  A.DNA testing should be systematized

  B.Only authorized laboratories can conduct DNA testing

  C.The academy only is authorized to work out standards for testing

  D.The academy has the right to accredit laboratories for DNA testing

  答案: CBABB

【英語(yǔ)四級(jí)考試閱讀復(fù)習(xí)指導(dǎo)】相關(guān)文章:

英語(yǔ)四級(jí)閱讀試題參考02-06

12月英語(yǔ)四級(jí)閱讀練習(xí)試卷:仔細(xì)閱讀12-19

英語(yǔ)四級(jí)閱讀理解練習(xí)題01-20

關(guān)于期末考試復(fù)習(xí)的英語(yǔ)復(fù)習(xí)方法08-16

6月大學(xué)英語(yǔ)四級(jí)閱讀理解題04-02

中考英語(yǔ)備考指導(dǎo)04-23

英語(yǔ)四級(jí)考試作文萬(wàn)能結(jié)尾句12-08

四級(jí)英語(yǔ)作文模板12-31

英語(yǔ)四級(jí)范文12-31

關(guān)于高考英語(yǔ)作文指導(dǎo)02-02

主站蜘蛛池模板: 亚洲αv在线精品糸列| 精品久久国产字幕高潮| 老熟女富婆激情刺激对白| 华人少妇被黑人粗大的猛烈进| 欧美国产日韩A在线视频| 日本免费人成视频在线观看| 国产初高中生在线视频| 国产精品JIZZ视频| 亚洲小说图片| 不卡无在线一区二区三区观| 亚洲日韩国产一区二区三区| 2019nv天堂香蕉在线观看| 国产精品偷伦视频免费观看了| 国产极品粉嫩馒头一线天AV| 精品一区二区三区在线观看| 99re6在线视频精品免费| 国产精品久久久久久久久岛国| 一本一本久久a久久精品综合| 欧美俄罗斯乱妇| 国产免费AV片在线观看| 国产免费破外女真实出血视频| 精品综合久久久久久97| 精品久久人妻AV中文字幕| 看曰本女人大战黑人视频| 国产老妇伦国产熟女老妇高清| 亚洲不卡AV不卡一区二区| 国产精品国三级国产AV| 中文字幕va一区二区三区| 少妇又色又紧又爽又刺激视频| 国产乱码精品一区二区三区中文| 不卡一卡二卡三乱码免费网站| 不卡无在线一区二区三区观| 国产高清在线精品一区| 老少配老妇老熟女中文普通话| 少妇三级全黄| 韩国日本三级在线观看| 少妇的渴望HD高清在线播放| 国产AV无码专区亚洲AV琪琪| 精品福利视频一区二区三区| 亚洲色精品三区二区一区| 中文无码日韩欧免费视频|