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武汉大学生命科学学院
2006-2007 学年度第二学期期末考试
《病毒学》A 试卷
姓名
学号
专业
得分
一．判断对错题，正确的选项请在括号中填写“╋”错误的选项填写“━”
（60*1=
60 分）
Are the following statements true or false?
（ +）1. Virus particles cannot generally be seen using light microscopes
（ -）2. Edward Jenner first vaccinated a patient against smallpox on 14th May 1976
（+ ）3. Louis Pasteur invented the term ‘virus’ in the 1890s
（ +）4. Dimitri Iwanowski showed that viruses could pass through filters fine
enough to retain the smallest known bacteria
（+ ）5. The vast majority of virus infections do not result in disease.
（ -）6. Viruses are submicroscopic, obligate intracellular parasites. This simple
definition excludes all other types of microorganism
（ + ）7. Virus particles (Virions) do NOT ‘grow’ or undergo division
（ +）8. Viruses lack the genetic information which encodes apparatus necessary for
the generation of metabolic energy
（ +）9. Viruses encode the genetic information which encodes apparatus necessary
for protein synthesis (ribosomes)
（ +）10. Prions are infectious agents believed to consist of a single protein
component
（ +）11. The poxvirus contains dsDNA genome and the particle structure is very
complex
（ -）12. Picornavirus particle contain more than 100 different proteins
（ -）13. The tailed bacteriophages are released from the host cell by budding
（ -）14. The tailed bacteriophages have separate assembly pathways for the head and
tail sections of the particle
（ +）15. Reovirus capsids are composed of a double protein shell
（ + ） 16. Matrix proteins are internal virion proteins that link the internal
nucleocapsid assembly to the envelope
（ +）17. Matrix proteins are often very abundant in the virus particle
（ +）18. External glycoproteins are usually the major antigens of enveloped viruses
（+ ） 19. External glycoproteins are usually the virus attachment proteins of
enveloped viruses
（ +）20. The influenza virus M2 peptide is a transmembrane protein
（ + ）21. Picornaviruses have icosahedral symmetry
（ +）22. Rhabdoviruses are helical enveloped viruses
（ +）23. The lipid composition of a virus envelope is similar to that of the host cell
（ +）24. Virus envelopes are acquired during budding of the particle through the host
cell membrane
（ -）25. Virus genomes vary in size from 300 nucleotides to approximately 300
kilobase pairs
（ +）26. The genetic code of a virus must be similar to that of the host organism so
that it can be decoded by the host cell biochemical machinery.
（ +）27. Virus genomes consisting of plus-sense RNA are infections when the
purified vRNA is applied to cells in the absence of any virus proteins.
（ +）28. Reverse genetics makes possible the manipulation of minus-sense RNA
virus genomes.
（ -）29. Infection of cells caused by nucleic acid alone is referred to as transduction
（ +）30. Mutation rates in herpesvirus genomes are low, similar to those seen in
cellular genomes
（ +）31. Mutation rates in retrovirus genomes are high due to the low fidelity of
reverse transcriptase.
（ +）32. Every new HIV provirus formed contains, on average, at least one new
mutation
（ +） 33. Temperature-sensitive (t.s.) mutations usually result from mis-sense
mutations in proteins
（ -）34. Superinfection is infection or a single cell by a very large virus particle.
（ + ） 35. The probability of recombination between two genetic markers is
proportional to the distance between them
（ +）36. In virus with segmented genomes, 'reassortment groups' are usually
equivalent to the individual genome segments.
（ +）37. Populations of virus genomes consisting of mixtures of molecular variants
are known as quasispecies.
（ + ） 38. Site-specific molecular biological methods are commonly used to
mutagenize virus genomes.
About retroviruses (true or false?):
（ + ） 39. Reverse transcriptase is also expressed by hepadnaviruses and
caulimoviruses.
（ +）40. Are the only RNA viruses whose genome is produced by cellular
transcriptional machinery.
（ +）41. Are the only plus-sense RNA viruses whose genome does not serve directly
as mRNA immediately after infection.
（ -）42. Have low mutation rates, due to the high fidelity of reverse transcriptase
（ +）43. Have a high rate of recombination, due to reverse transcription.
（
（
（
（
+）44. Virus penetration of cells is an energy-dependent process.
+）45. influenza haemagglutinin is a virus fusion protein.
-）46. Uncoating only occurs in the nucleus of the host cell.
+）47. The product of uncoating is usually a complex of nucleic acids and virus
proteins.
（ -）48. Nucleoproteins associated with virus genomes are responsible for cell
penetration.
（ -）49. Virus receptor molecules are always proteins.
（ -）50. Most viruses have more than one receptor molecular.
（ +）51. No known plant virus used a cellular receptor.
（ +）52. Sialic acid is the influenza virus receptor.
（ +）53. The expression of receptors on the surface of cells is the major factor which
determines the tropism of viruses.
（ -）54. Adenoviruses encode their own DNA polymerase.
（ + ）55. Poxviruses encode their own DNA polymerase and are independent of
cellular enzymes for genome replication.
（ +）56. Reovirus genomes are transcribed by a virus enzyme present in the particle.
（ -）57. All RNA virus genomes are replicated in the nucleus of the host cell.
（ +）58. Retrovirus genomes are transcribed by cellular RNA polymerase.
（ +）59. Reovirus transcription occurs inside virus core particles.
（ -）60. Segmented virus genomes are usually transcribed to produce polycistronic
mRNAs.
二．问答题
1．根据病毒基因组以及复制方式的不同，病毒可分为几大类？ （10 分）
全部答对得 10 分，答对 1 个得 1 分，答对 6 个得 6 分，一次类推
（1）dsDNA
（2）ssDNA
（3）dsRNA
（4）ssRNA(-)
（5）ssRNA(+)
（6）ssRNA, 有 DNA 复制中间体
（7）dsDNA, 有 RNA 复制中间体
2．病毒入侵宿主细胞，在遭受免疫系统的攻击后，有哪些策略逃避免疫应答？
（10 分）
(1) MHC 1 型抗原递呈的抑制，逃脱 CTL 反应
(2) MHC II 型抗原递呈的抑制，
(3) NK 细胞溶细胞作用的抑制
(4) 细胞因子作用的抑制（病毒编码受体，病毒因子）
(5) 阻断干扰素引发的信号转导
(6) 对体液免疫的逃逸，病毒蛋白的变异
(7) 对补体联级反映的逃逸
3．请画图描述病毒的一步生长曲线，并解释曲线的不同阶段所代表的意义（10
分）
隐蔽期
潜伏期
释放期
4．逆转录病毒与 DNA 肿瘤病毒都可以引起细胞转化，请比较两类病毒引起细
胞转化的机制有何不同。（10 分）
能够转化细胞的逆转录病毒分为三类：转换、顺式作用 和反式作用。
（1）转换：来自复制缺陷、急性转化的逆转录病毒所产生的原癌蛋白都是融合
蛋白，包含有源于病毒基因的附加序列，一般病毒的 gag 序列位于蛋白质的 N
末端。这些附加序列可能改变蛋白质的功能或细胞内的定位，这些改变可能导致
转化。
（2）顺式作用
慢性转化逆转录病毒不含有致癌基因，它们通过插入激活细胞中癌基因表达
（3）反式作用
病毒编码一种转录激活物蛋白如 tax 基因编码蛋白，通过反式作用来刺激细胞内
癌基因的转录
DNA 肿瘤病毒通过与
（4）P53 和
（5）Rb 相互作用，改变细胞周期，从而使细胞转化