【医学类职业资格】中山大学2003-2004学年第一学期细胞生物学期中考试试题及答案解析.doc

1、中山大学 2003-2004学年第一学期细胞生物学期中考试试题及答案解析(总分：110.00，做题时间：90 分钟)一、填空题(每空 0(总题数：5，分数：5.00)1.决定红细胞 ABO血型的物质是糖脂，它由脂肪酸和寡糖素链组成。A 型血糖脂上的寡糖链较 O型多一个 ；B 型血仅多一个 。（分数：1.00）填空项 1:_2.根据题意, 将与 A、B、C、D 相对应的词用连线连起来: Cells communicate in ways that are analogous to human communication. Decide which of the following forms o

2、f human communication are analogous to autocrine, paracrine, endocrine, and synaptic signaling by cells. A. A telephone conversation: autocrine B. Talking to people at a cocktail party: endocrine C. A radio announcement: synaptic signaling D. Talking to yourself : paracrine （分数：1.00）3. What is the m

3、ajor factor that determines the limit of resolution of a light microscope?（分数：1.00）填空项 1:_4.编码载脂蛋白 B的基因在肠组织中转录成 mRNA后,第 2153位的 C被 形成 U,使 CAA密码转变成终止密码 UAA, 使翻译提前终止。（分数：1.00）填空项 1:_5. 是细胞外基质的受体蛋白。在结构上，它们是异二聚体，。这种跨膜蛋白的细胞外部分有一个球形的头部，可与细胞外基质蛋白结合，而细胞质结构域则可与 相结合。（分数：1.00）填空项 1:_二、判断以下各题是否正确, 若正确, 用 T表(总题数：

4、10，分数：10.00)6.Both the GTP-bound a subunits and nucleotide-free b? complexes, but not GDP-bound, fully assembled G proteins, activate other molecules downstream of G-protein-linked receptors. （分数：1.00）A.正确B.错误7.The density of water is less than the density of ice.（分数：1.00）A.正确B.错误8.Water has a high

5、specific heat.（分数：1.00）A.正确B.错误9. There is no fundamental distinction between signaling molecules that bind to cell-surface receptors and those that bind to intracellular receptors. （分数：1.00）A.正确B.错误10.How is it that different cells can respond in different ways to exactly the same signaling molecul

6、e even when they have identical receptors? （分数：1.00）A.正确B.错误11. Protein kinase A itself is different in different cell types, which explains why the effects of cyclic AMP vary depending on the target cell. （分数：1.00）A.正确B.错误12.It is thought that extracellular ligand binding to a receptor tyrosine kin

7、ase activates the intracellular catalytic domain by propagating a conformational change across the lipid bilayer through the single transmembrane a helix. （分数：1.00）A.正确B.错误13.Atrial natriuretic peptides(心钠肽) bind to a receptor that activates a G protein,which in turn activates guanylyl cyclase(鸟苷环化酶

8、) to produce cyclic GMP which then activates a cyclic GMP-dependent protein kinase (PKG). （分数：1.00）A.正确B.错误14. Because prokaryotic cells have neither mitochondria nor chloroplasts, they cannot carry out either ATP synthesis or photosynthesis. （分数：1.00）A.正确B.错误15.电镜的波长与电压有关，电压越高，波长越短，分辨率越高。 （分数：1.00）

9、A.正确B.错误三、选择题(请将正确答案的代号填入括号)(总题数：15，分数：15.00)16.Which one of the following is incorrect for the biogenesis of eukaryotic ribosomes?( ) （分数：1.00）A.25-50% of the pre-rRNA is degradedB.Pre-rRNA binds to ribosomal proteinC.Pre-rRNA is cut to form three classes of rRNAD.Pre-rRNA is methylatedE.The rRNA g

10、ene for the 40S subunit is transcribed separately17. The 5S rRNA differs from the other cellular rRNAs in which of the following ways? ( ) （分数：1.00）A.The genes are located outside the nucleolus(核仁).B.The genes are transcribed by RNA polymerase III.C.The promoter region of the 5S rRNA gene is interna

11、l to the gene.D.all of the above18.钙泵的作用主要是( )。 （分数：1.00）A.降低细胞质中 Ca2+的浓度；B.提高细胞质中 Ca2+的浓度；C.降低内质网中 Ca2+的浓度；D.降低线粒体中 Ca2+的浓度19. Plant guard cells(保卫细胞) have a higher C1- than the outside environment. The most likely explanation for this is( ). （分数：1.00）A.Water leaves the cell by osmosis.B.C1- is dif

12、fusing through transmembrane channels.C.C1- diffusion is aided by a mobile carrier.D.An active transport symport transports C1-/H+.E.None of the above20.The hormone glucagons(胰高血糖素) stimulates the breakdown of stored glycogen in liver and muscle cells by the following enzymes. Which is the first enz

13、yme that must be activated? ( ) （分数：1.00）A.Protein kinase AB.Phosphorylase kinaseC.Glycogen phosphorylaseD.Protein phosphataseE.Protein phosphatase inhibitor-121.在下列组织中, 紧密连接特别重要的有( ) （分数：1.00）A.Stomach(胃) and kidneysB.Smooth muscleC.Heart muscleD.Intestinal epithelial tissue(肠表皮组织)22.Which one of t

14、he following was used to determine the structure of the DNA molecule? ( ) （分数：1.00）A.Transmission(透射) electron microscopeB.Scanning electron microscopeC.Differential centrifugatioin(差速离心)D.X-ray crystallography23. A eukaryotic cell has( ) （分数：1.00）A.One copy of each ribosomal transcription unit.B.Th

15、ousands of copies of the 5S rRNA gene.C.Two copies of each gene for rRNA and ribosomal proteins.D.Two copies of each gene for rRNA and one copy of each ribosomal proteingene.24.All of the following are true about antisense RNA except ( ) （分数：1.00）A.Is complementary to mRNA.B.Forms double-stranded RN

16、A.C.Joins with the 30S subunit.D.Inhibits protein synthesis.25. Developing frog embryos treated with anti-fibronectin antibodies （分数：1.00）A.Develop normally.( )B.Stop cell division.C.Have abnormal cell migration(迁移).D.Dont exhibit action potentials.26.肌动蛋白纤维对于黏着斑就像( )对于半桥粒。 （分数：1.00）A.肌球蛋白纤维B.角蛋白纤维C

17、.微丝D.钙粘着蛋白27.配体(ligand)是（ ）。 （分数：1.00）A.酶与底物共价结合的活性位点；B.酶与底物非共价结合的活性位点；C.对于一个与蛋白质以共价形式相作用的小分子的普遍称呼；D.对于一个与蛋白质以非共价形式相作用的小分子的普遍称呼；E.一个缺乏酶活性的球蛋白28.膜胆固醇的组成与质膜的性质、功能有着密切的关系,（ ） （分数：1.00）A.胆固醇可防止膜磷脂氧化；B.正常细胞恶变过程中，胆固醇/磷脂增加；C.胆固醇/磷脂下降，细胞电泳迁移率减少；D.在质膜相变温度以下，增加胆固醇，可以提高膜的流动性29.用抗纤连蛋白的抗体注射胚体，发现在神经系统发育过程中神经嵴细胞的迁

18、移受到抑制。这些实验说明：( ) （分数：1.00）A.神经嵴发育包括抗体基因的表达；B.发育中的神经无需合成纤连蛋白；C.纤连蛋白/抗体复合物形成神经细胞的迁移途径；D.胚胎中的神经元在移动过程中必须与纤连蛋白暂时结合30.当胰岛素与其受体酪氨酸激酶结合后，随后发生的事件是( )。 （分数：1.00）A.IRS的结合具有 SH2区域的蛋白质的磷酸化效应；B.与具有 SH2区域的蛋白质结合IRS 的磷酸化效应；C.自磷酸化并将 IRS磷酸化与具有 SH2区域的蛋白质结合效应；D.自磷酸化并与 IRS结合将具有 SH2区域的蛋白质磷酸化效应四、简答题(每题 4分，共 40分)(总题数：10，分数

19、：40.00)31. What functional roles do the ECM (细胞外基质)and cell wall share in common? （分数：4.00）_32. Discuss the following analogy(相似): “The differences between transporting a ligand by a channel or a carrier protein are like the differences between crossing a river by a bridge or a ferry(摆渡).“ （分数：4.00）

20、_33.EGTA chelates(螯合) Ca2+ with high affinity and specificity. How would microinjection(微注射) of EGTA affect glucagon-triggered breakdown of glycogen (糖原) in liver? （分数：4.00）_34. The basic structure of biological membranes is determined by the lipid bilayer, but their specific functions are carried o

21、ut largely by proteins. Explain your answer. （分数：4.00）_35.Why does a red blood cell membrane need proteins?（分数：4.00）_36. Describe the different methods that cells use to restrict proteins to specific regions of the plasma membrane. Is a membrane with many anchored proteins still fluid? （分数：4.00）_37.

22、 Transport by carrier proteins can be either active or passive, whereas transport by channel proteins is always passive. Explain your answer. （分数：4.00）_38.The signaling mechanisms used by a steroid-hormone(固醇激素) receptor and by an ion-channel-linked receptor have very few components(组分). Can either

23、mechanism lead to an amplification of the initial signal? If so, how? （分数：4.00）_39.Should RGS (regulator of G protein signaling) proteins be classified as GEFs (guanine nucleotide exchange factors) or GAPs (GTPase activating proteins)? Explain what role this activity plays in modulating G-protein-me

24、diated responses in animals and yeasts. （分数：4.00）_40.How is an IP3-triggered Ca2+ response terminated?（分数：4.00）_41.简述第二信使 cAMP的发现及生成的实验证明(20 分)。（分数：20.00）_六、分析与思考(任选一题, 20 分)(总题数：2，分数：20.00)42.Why do you suppose that phosphorylation/dephosphorylation, plays such a prominent role in switching protein

25、s on and off in signaling pathways?（分数：10.00）_43.The Ras protein functions as a molecular switch that is set to its on state by a guanine-nucleotide exchange factor (GEF) that causes it to bind GTP. A GTPase-activating protein (GAP) resets the switch to the off state by inducing Ras to hydrolyze its

26、 bound GTP to GDP much more rapidly than in the absence of the GAP. Thus Ras works like a light switch that one person turns on and another turns off. In a cell line that lacks the Ras-specific GAP, what abnormalities would you expect to find in the way Ras activity responds to extracellular signals

27、? （分数：10.00）_中山大学 2003-2004学年第一学期细胞生物学期中考试试题答案解析(总分：110.00，做题时间：90 分钟)一、填空题(每空 0(总题数：5，分数：5.00)1.决定红细胞 ABO血型的物质是糖脂，它由脂肪酸和寡糖素链组成。A 型血糖脂上的寡糖链较 O型多一个 ；B 型血仅多一个 。（分数：1.00）填空项 1:_ （正确答案：N-乙酰半乳糖胺残基，半乳糖残基）解析：2.根据题意, 将与 A、B、C、D 相对应的词用连线连起来: Cells communicate in ways that are analogous to human communication

28、. Decide which of the following forms of human communication are analogous to autocrine, paracrine, endocrine, and synaptic signaling by cells. A. A telephone conversation: autocrine B. Talking to people at a cocktail party: endocrine C. A radio announcement: synaptic signaling D. Talking to yoursel

29、f : paracrine （分数：1.00）解析：3. What is the major factor that determines the limit of resolution of a light microscope?（分数：1.00）填空项 1:_ （正确答案：波长）解析：4.编码载脂蛋白 B的基因在肠组织中转录成 mRNA后,第 2153位的 C被 形成 U,使 CAA密码转变成终止密码 UAA, 使翻译提前终止。（分数：1.00）填空项 1:_ （正确答案：脱氨）解析：5. 是细胞外基质的受体蛋白。在结构上，它们是异二聚体，。这种跨膜蛋白的细胞外部分有一个球形的头部，可与细

30、胞外基质蛋白结合，而细胞质结构域则可与 相结合。（分数：1.00）填空项 1:_ （正确答案：整联蛋白 肌动蛋白纤维）解析：二、判断以下各题是否正确, 若正确, 用 T表(总题数：10，分数：10.00)6.Both the GTP-bound a subunits and nucleotide-free b? complexes, but not GDP-bound, fully assembled G proteins, activate other molecules downstream of G-protein-linked receptors. （分数：1.00）A.正确 B.错误

31、解析：bg 复合物能够激活离子通道, 结合有 GTP的亚基能够激活酶。7.The density of water is less than the density of ice.（分数：1.00）A.正确B.错误 解析：错误。冰的密度比水低。这样就保证冰能够漂浮在水的表面, 并在温度升高超过冰点时化冰。 8.Water has a high specific heat.（分数：1.00）A.正确 B.错误解析：正确。高比热意味着需要较多的热才能升高温度。这就有效地缓冲了细胞对周围环境温度而保持细胞温度的稳定。9. There is no fundamental distinction bet

32、ween signaling molecules that bind to cell-surface receptors and those that bind to intracellular receptors. （分数：1.00）A.正确B.错误 解析：错误。与细胞表面受体结合的信号分子不必跨过质膜, 因此, 此类信号分子可 大可小, 疏水或亲水。但与细胞内受体结合的信号分子必须足够小和疏水。10.How is it that different cells can respond in different ways to exactly the same signaling molec

33、ule even when they have identical receptors? （分数：1.00）A.正确 B.错误解析：主要是不同的细胞对信号反应的内部机制不同。既便是反应途径相同, 不同的细胞也会表达不同的蛋白质进行应对。 11. Protein kinase A itself is different in different cell types, which explains why the effects of cyclic AMP vary depending on the target cell. （分数：1.00）A.正确B.错误 解析：错误。是因为不同细胞中 PK

34、A的底物不同, 而不是蛋白激酶 A的不同。 12.It is thought that extracellular ligand binding to a receptor tyrosine kinase activates the intracellular catalytic domain by propagating a conformational change across the lipid bilayer through the single transmembrane a helix. （分数：1.00）A.正确B.错误 解析：错误。配体与受体酪氨酸激酶的结合引起二聚体的装配。

35、任何受体进行自磷酸化, 从而启动细胞内的信号级联反应。在某些情况下, 如胰岛素受体, 通过细胞外的两个受体形成二聚体, 然后通过两个 螺旋进行构型的变化。 13.Atrial natriuretic peptides(心钠肽) bind to a receptor that activates a G protein,which in turn activates guanylyl cyclase(鸟苷环化酶) to produce cyclic GMP which then activates a cyclic GMP-dependent protein kinase (PKG). （分数：

36、1.00）A.正确B.错误 解析：错误。心钠肽直接与受体鸟苷环化酶结合, 将之激活, 并由激活的鸟苷环化酶产生 cGMP, 再由cGMP激活 PKG。14. Because prokaryotic cells have neither mitochondria nor chloroplasts, they cannot carry out either ATP synthesis or photosynthesis. （分数：1.00）A.正确B.错误 解析：错误。原核细胞同样能进行 ATP的合成和光合作用。只不过不是通过细胞内的区室, 而是通过中膜体之类的结构。 15.电镜的波长与电压有关，

37、电压越高，波长越短，分辨率越高。 （分数：1.00）A.正确 B.错误解析：三、选择题(请将正确答案的代号填入括号)(总题数：15，分数：15.00)16.Which one of the following is incorrect for the biogenesis of eukaryotic ribosomes?( ) （分数：1.00）A.25-50% of the pre-rRNA is degradedB.Pre-rRNA binds to ribosomal proteinC.Pre-rRNA is cut to form three classes of rRNAD.Pre-

38、rRNA is methylatedE.The rRNA gene for the 40S subunit is transcribed separately 解析：17. The 5S rRNA differs from the other cellular rRNAs in which of the following ways? ( ) （分数：1.00）A.The genes are located outside the nucleolus(核仁).B.The genes are transcribed by RNA polymerase III.C.The promoter reg

39、ion of the 5S rRNA gene is internal to the gene.D.all of the above 解析：18.钙泵的作用主要是( )。 （分数：1.00）A.降低细胞质中 Ca2+的浓度； B.提高细胞质中 Ca2+的浓度；C.降低内质网中 Ca2+的浓度；D.降低线粒体中 Ca2+的浓度解析：19. Plant guard cells(保卫细胞) have a higher C1- than the outside environment. The most likely explanation for this is( ). （分数：1.00）A.Wat

40、er leaves the cell by osmosis.B.C1- is diffusing through transmembrane channels.C.C1- diffusion is aided by a mobile carrier.D.An active transport symport transports C1-/H+. E.None of the above解析：20.The hormone glucagons(胰高血糖素) stimulates the breakdown of stored glycogen in liver and muscle cells by

41、 the following enzymes. Which is the first enzyme that must be activated? ( ) （分数：1.00）A.Protein kinase A B.Phosphorylase kinaseC.Glycogen phosphorylaseD.Protein phosphataseE.Protein phosphatase inhibitor-1解析：21.在下列组织中, 紧密连接特别重要的有( ) （分数：1.00）A.Stomach(胃) and kidneys B.Smooth muscleC.Heart muscleD.I

42、ntestinal epithelial tissue(肠表皮组织)解析：22.Which one of the following was used to determine the structure of the DNA molecule? ( ) （分数：1.00）A.Transmission(透射) electron microscopeB.Scanning electron microscopeC.Differential centrifugatioin(差速离心)D.X-ray crystallography 解析：23. A eukaryotic cell has( ) （分数

43、：1.00）A.One copy of each ribosomal transcription unit.B.Thousands of copies of the 5S rRNA gene. C.Two copies of each gene for rRNA and ribosomal proteins.D.Two copies of each gene for rRNA and one copy of each ribosomal proteingene.解析：24.All of the following are true about antisense RNA except ( )

44、（分数：1.00）A.Is complementary to mRNA.B.Forms double-stranded RNA.C.Joins with the 30S subunit. D.Inhibits protein synthesis.解析：25. Developing frog embryos treated with anti-fibronectin antibodies （分数：1.00）A.Develop normally.( )B.Stop cell division.C.Have abnormal cell migration(迁移). D.Dont exhibit ac

45、tion potentials.解析：26.肌动蛋白纤维对于黏着斑就像( )对于半桥粒。 （分数：1.00）A.肌球蛋白纤维B.角蛋白纤维 C.微丝D.钙粘着蛋白解析：27.配体(ligand)是（ ）。 （分数：1.00）A.酶与底物共价结合的活性位点；B.酶与底物非共价结合的活性位点；C.对于一个与蛋白质以共价形式相作用的小分子的普遍称呼；D.对于一个与蛋白质以非共价形式相作用的小分子的普遍称呼； E.一个缺乏酶活性的球蛋白解析：28.膜胆固醇的组成与质膜的性质、功能有着密切的关系,（ ） （分数：1.00）A.胆固醇可防止膜磷脂氧化；B.正常细胞恶变过程中，胆固醇/磷脂增加；C.胆固醇/磷脂下降，细胞电泳迁移率减少；D.在质膜相变温度以下，增加胆固醇，可以提高膜的流动性 解析：29.用抗纤连蛋白的抗体注射胚体，发现在神经系统发育过程中神经嵴细胞的迁移受到抑制。这些实验说明：( ) （分数：1.00）A.神经嵴发育包括抗体基因的表达；B.发育中的神经无需合成纤连蛋白；C.纤连蛋白/抗体复合物形成神经细胞的迁移途径； D