DNA的高级结构是

A:直线结构 B:螺旋结构 C:微螺旋结构 D:超螺旋结构 E:折叠结构

为研究肺癌患者肺组织中的DNA加合物含量（个／10核苷酸）与吸烟的关系，某研究者用"同位素标记法"测定了12名肺癌患者肺组织中DNA加合物含量(y)，并调查其每日吸烟量(x)，结果如下表。

以每日吸烟量为自变量χ，肺组织中DNA加合物含量为应变量y进行直线回归分析，则要求

A:肺组织中DNA加合物含量来自于正态总体 B:肺组织中DNA加合物含量可以来自于分布类型未知总体 C:每日吸烟量和肺组织中DNA加合物含量必须都来自于正态总体 D:每日吸烟量和肺组织中DNA加合物含量可以来自于对数正态分布 E:每日吸烟量和肺组织中DNA加合物含量其中之一来自于正态总体

DNA Fingerprinting

    DNA is the genetic material found within the cell nuclei of all living things. In mammals the strands of DNA are grouped into structures called chromosomes.¹ With the exception of identical siblings (as in identical twins)²，the complete DNA of each individual is unique.

    DNA fingerprinting is sometimes called DNA typing.³ 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. The sample is then segmented using enzymes, 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.⁴ 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 diseases⁵，it soon came to be used in criminal investigations and legal affairs. The first criminal conviction based on DNA evidence⁶ in the United Statesoccurred 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.

词汇：

figerprinting /ˈfɪŋgəprɪnt/ n. 指纹法，指纹术 

nucleus /"nju:klɪəs/ n. 核，中心
genetic / dʒəˈnetɪk / adj. 遗传的 

mammal /ˈmæml/ n. 哺乳动物
chromosome /ˈkrəʊməˌsəʊm/ n. 染色体 

identification /"aɪˌdentɪfɪˈkeɪʃn/ n. 识别，鉴定，证明
enzyme /"enzaɪm/ n. 酶 

suspect /səˈspekt/ n. 嫌疑犯
fingerprint / ˈfɪŋgəprɪnt / n. 指纹 

saliva /səˈlaɪvə/ n. 唾液
segment /ˈsegmənt/ vt.  分割，分裂；切片，不笨
controversial / ˌkɒntrəˈvɜ:ʃl / adj. 有争议的 

uniform /"ju:nɪfɔ:ml/ adj. 一致的，相同的

注释：

1.In mammals the strands of DNA are grouped into structures called chromosomes.哺乳L动物的 DNA线被组合为称作染色体的各种结构。
2.With the exception of identical siblings (as in identical twins)：生物姊妹体除外（如完全相同的双胞胎）
3.DNA fingerprinting is sometimes called DNA typing. DNA 指纹检查法有时也称 DNA 印记法。
4.The segments are marked with probes and exposed on X-ray film, where they form a pattern of black bars - the DNA fingerprint.切片先用探针做标记，然后在X光片上曝光。胶片上形成 由黑色条纹组成的图案，这就是DNA指纹。
5.Originally used to detect the presence of genetic diseases ： (DNA 指纹法）开始是用来探测遗传病的存在
6.The first criminal conviction based on DNA evidence：基于 DNA 提供证据的首例定罪

This essay talks about DNA fingerprinting concerning the following aspects EXCEPT____

A:legal application of the method B:the way to obtain a DNA sample C:work yet to be done about DNA fingerprinting D:possible danger in drawing a DNA sample from the human body

下列关于DNA的结构错误的是（）。

A:DNA一级结构就是脱氧核苷酸按照一定排列顺序的线性结构 B:多数DNA是双链结构，少数是单链结构，并且所有DNA都是线性结构 C:DNA具有双螺旋，三链，四链结构的多态性二级结构 D:超螺旋是DNA的三级结构

DNA的双螺旋结构属于（）

A:DNA的一级结构 B:DNA的二级结构 C:DNA的三级结构 D:DNA的四级结构 E:DNA的五级结构

按（　　）划分，结构化金融衍生产品分为利率联结型产品、股权联结型产品(其收益与单只股票，股票组合或股票价格指数相联系)、汇率联结型产品、商品联结型产品。

A:联结的金融基础产品 B:收益保障性 C:发行方式 D:价格决定方式

DNA的三级结构是

A:核小体串珠结构 B:双螺旋模型 C:Z-DNA锯齿结构 D:染色体结构

DNA的三级结构是（）

A:核小体串珠结构  B:双螺旋模型  C:Z-DNA锯齿结构  D:染色体结构

DNA的高级结构是（）

A:直线结构 B:螺旋结构 C:微螺旋结构 D:超螺旋结构 E:折叠结构