核酸的性质及染色体的结构 试题.docx

2-核酸的性质及染色体的结构
1. 在核酸分子中核苷酸之间是靠以下哪种化学键连接的？
A. 2’-3’磷酸二酯键 B. 2’-5’磷酸二酯键
C. 3’-5’磷酸二酯键 D. 糖苷键
2. 以下哪条序列是与AGTCTGACT的DNA序列对应的RNA序列？
A. AGUCUGACU B. UGTCTGUTC
C. UCAGUCUGA D. AGUCAGACU
3. 下列哪条符合B-型DNA的特征？
A. 右手反向双螺旋，每螺旋10 bp，碱基垂直于螺旋轴
B. 左手反向双螺旋，每螺旋12 bp，由嘧啶-嘌呤序列交替形成
C. 右手反向双螺旋，每螺旋11 bp，碱基倾斜于螺旋轴
D. 由单链核酸形成的分子内螺旋构成的球状结构
4. 双链DNA的解链温度（Tm）是指_____.
A.双链DNA开始解链的温度　
　Ｂ．双链DNA充分解链的温度
Ｃ．可以造成双链DNA解链的温度范围
Ｄ．半数双链DNA解链的温度
５.　双链DNA变性包括_____.
A. DNA断裂成短的片段 B.双链分开成单链
C. DNA骨架的水解 D. 碱基从糖-磷酸骨架上断裂
6. 以下哪种在光波长为260 nm时，单位质量的吸光值最大？
A.双链DNA B.单核苷酸 C. RNA D.蛋白质
7. 拓扑异构酶I…
A.改变2个连接数 B. 需要ATP
C.断裂DNA双螺旋上的一条链 D.是抗菌药的靶点
8. 维持DNA双螺旋结构稳定性的因素有哪些？
What contribute to the stability of nucleic acids?
Hydrolysis and denaturation
Buoyant density
Hypochromicity and hyperchromicity
Renaturation and hybridization
melting temperature or Tm
DNA supercoiling
DNA toposomeration, topoisomerase, topoisomers
1. 以下哪项是E.coli和真核生物染色体的共同特征？
A. DNA是环状的 B. DNA包装成核小体
C.DNA是包含在细胞核里 D.DNA是负超螺旋的
2. 166bp的DNA与组蛋白八聚体加上H1被称为什么？
A.核小体核心 B.螺线管 C.30 nm纤丝 D. 染色小体
3. 转录发生在间期染色体的哪个区域？
A.端粒 B.着丝粒 C.常染色质 D.异染色质
4. 关于CpG岛和甲基化，以下哪项是不正确的？
A. CpG岛对Dnase I特别有抗性
B. 真核生物中，CpG甲基化是造成CpG突变成TpG的根源
C. CpG岛在活跃基因的启动子附近存在
D. CpG甲基化与不活跃的染色质相关
5. 以下哪项是高度重复DNA的例子？
A.Alu 元件 B. 组蛋白基因簇 C.DNA微卫星 D.分散重复DNA
6. 原核与真核细胞基因组各有什么特点？
7. 组蛋白都有哪些类型的修饰，其功能分别是什么？
8. 真核DNA分子是如何包装成染色体的？
9. 什么是SNP？
Diagram a nucleosome as follows: (a) on a drawing of the histones without the DNA, show through positions of all the histones. (b) On a separate drawing, show the path of DNA around the histones.
Where does the transcription take place during interphase, heterochromatin or euchromatin?
What is CpG methylation?
How is eukaryotic DNA compacted into nucleus?
What are the differences between eukaryotic chromosome and prokaryotic chromosome?
Explain why brief digestion of eukaryotic chromatin with micrococcal nuclease gives DNA fragments 200 bp long, but longer digestion yields 146 bp fragments.
3-DNA复制及损伤修复
1. 请简述DNA复制的机制。
2. DNA复制的酶学特征
3. 有哪些蛋白参与了大肠杆菌的DNA复制？
4. 大肠杆菌是如何起始复制的？
5. 什么是端粒？请阐述端粒复制的原理。
6. 维持DNA复制忠实性的因素有哪些？
7. 典型哺乳动物细胞的复制子数量是…
A. 40-200 B. 400 C. 1000-2000 D. 50000-100000
8. 在原核细胞中，后随链的引物是被…切除的？
A. 3’-5’外切酶 B. DNA连接酶 C. DNA聚合酶I D. DNA聚合酶III
9. 在E. coli复制原点的起始蛋白是… ？
A. DnaA B. DNAB C. DnaC D. DnaE
10. 原核的质粒能在酵母中复制如果它含有一个克隆的酵母…
A. ORC B. CDK C. ARS D.RNA
11. 每加入一个核苷酸，E.coli的自发突变率是多少？
A. 1/106 B. 1/108 C. 1/109 D. 1/1010
12. 在甲基指引的E.coli的错配修复中，含错配碱基的子链是被什么切开的？
A. MutH内切酶 B. UvrABC内切酶
C. AP内切酶 D. 3’-5’外切酶
13. 异常重组的另一种名称是什么？
A. 位点特异性重组 B. 转座作用
C. 同源重组 D. 跨损伤修复
14. UV引起的DNA损伤的切除修复能力缺失的人有什么病？
A. 遗传的非息肉病性大肠癌 B.克罗恩氏病
C. 经典色素性干皮症 D.色素性干皮症的变异型
4-基因操作
Why do we need to attach DNAs to vectors to clone them？
Describe the process of cloning a DNA fragment into the BamHI and PstI sites of the vector pUC18. How would you screen for clones that contain an insert?
What kind of vector would you use to insert a foreign gene into a plant such as tobacco? Diagram the process you would use.
You want to make a genomic library with DNA fragments averaging about 40 kb in length. Which vector would be most appropriate to use?Why?
Describe the use of a baculovirus system for expressing a cloned gene. What advantages over a prokaryotic expression system does the baculovirus system offer?
5-克隆载体和基因文库
什么是DNA克隆？它的主要步骤是什么？
哪两种方法可以避免载体的自身连接现象？
作为克隆载体和表达载体的质粒各需要具备哪些条件？
蓝白斑筛选的原理是什么？
基因工程中常用α-互补来筛选重组质粒，请说明原理。
在细菌中是否存在一种质粒，通常用什么方法检测？
A.蓝白斑筛选 B.在有抗生素的培养基中生长
C.限制性内切酶酶切 D. 琼脂糖凝胶电泳
7. 碱性磷酸酶的作用是。。。
A.连接DNA双链　 B.加一个磷酸基团到DNA的5’端
C. 切断双链DNA D. 从DNA的5’端去掉一个磷酸基团
8. 转化是…
A. 细菌吸收质粒　　Ｂ．基因在细菌中表达
　 Ｃ．细菌吸收噬菌体　Ｄ．从细菌中分离质粒
9. 要在植物细胞中表达一种外源基因，以下哪种载体适用？
Ａ．杆状病毒 B. 反转录病毒 C. pUC19 D. T载体
10. 要克隆一段18 kb的DNA分子，以下哪种载体适用?
A. 质粒 B. λ噬菌体 C. 细菌人工染色体 D.酵母人工染色体
Why do we need to attach DNAs to vectors to clone them？
Describe the process of cloning a DNA fragment into the BamHI and PstI sites of the vector pUC18. How would you screen for clones that contain an insert?
What kind of vector would you use to insert a foreign gene into a plant such as tobacco? Diagram the process you would use.
You want to make a genomic library with DNA fragments averaging about 40 kb in length. Which vector would be most appropriate to use? Why?
Describe the use of a baculovirus system for expressing a cloned gene. What advantages over a prokaryotic expression system does the baculovirus system offer?
Diagram a method for creating a cDNA library.
Diagram the process of Southern blotting and probing to detect a DNA of interest. Compare and contrast this procedure with Northern bloting.
What are the advantages of cDNA library over genomic library?
7-原核的转录与调控
复制和转录有何异同？
催化E. coli基因转录的酶是什么？有何结构特征？
RNA聚合酶特异性结合及转录起始所需的保守序列叫做什么？有何结构特征？
E. coli是如何终止转录的？
什么是操纵子？画出乳糖操纵子和色氨酸操纵子的结构，阐述这两个操纵子是如何调控基因表达的？
什么是弱化子？什么是弱化作用？
15-transcription+2
What are the major RNA polymerases in Eukaryote? What are their functions?
What are the differences in initiation of transcription between prokaryotes and eukaryotes?
Describe the main kinds of promoters in eukaryotes.
What are CTD, TBP?
16-regulation of transcription in eukaryotes2
What are the helix-turn-helix domain, zinc fingers domain and leucine zipper domain?
How do the steroid hormones regulate transcription?
How does interferon-γ regulate transcription by phosphorylation of an transcription factor STAT1α ?
What’s cell determination? How to regulate cell determination by regulation of MyoD gene expression?
17-RNA processing
What’s RNA processing? Describe the main ways of RNA processing?　
什么是RNA加工？描述RNA加工的主要方式？
What does the word “split gene” mean?
“割裂基因”是什么意思？
What kinds of RNA processing are carried out for hnRNA to become mRNA?
从hnRNA到mRNA经过了哪些加工？
What are the functions of mRNA cap?
mRNA帽的功能是什么？
What is polyadenylation？Which roles does it play？
什么是多聚腺苷酸化？它的功能是什么？
What’s splicing in RNA processing?
什么是RNA加工中的剪接？
What’s alternative mRNA processing？List the main ways for alternative splicing.
什么是mRNA可变加工？列出可变剪切所利用的主要方式。
What’s RNA editing?　
什么是RNA编辑？
What’s ribozymes? 什么是核酶？
18-genetic code and tRNA
What are the properties of codon?
　　密码子有何特性？
What’s　open　reading　frame? 什么是开放阅读框（可读框、编码区）？
What’s overlapping genes?　什么是重叠基因？
What’s the function of tRNA? Describe the properties of secondary structure of tRNA.　tRNA的功能是什么？它的二级结构有何特点？
How does aminoacylation of tRNAs occur?
tRNA的氨酰化作用是如何发生的?
What’s the Wobble hypothesis? 什么是Wobble假说（摆动假说）？
What’s the difference between the Initiator tRNA and normal tRNAMet
19-蛋白质的生物合成
1.What are the differences in the initiation of translation between prokaryotes and eukaryotes？ 原核和真核生物之间转译的起始有何不同？
2. What’s signal peptide？什么是信号肽？
3. List the main kinds of modifications post translation. 列出转译后修饰的主要类型。
4. Describe the amino-acylation of tRNAs.
5. Describe the main steps of elongation in protein synthesis in prokaryotes.
6. How does protein synthesis terminate?