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(三) 利用生物技术手段借助萤火虫的发光基因，美国弗吉尼亚大学史蒂夫·凯博：上的研究小组鉴定出第一个植物生物钟基因。 长期以来，科学家们一直在探索植物周期行为——生理节律的奥秘。虽然这些行为与环境条件有密切关系，如光照长短等，但植物学家一直认为生物钟是植物感知外界条件的决定因素。要鉴定生理节律的生物钟基因，通常有两个关键问题：第一，生理节律能否被检测到；第二，需找到这种生理节律的异步个体。植物光合作用节律常规方法是难以检测的，史蒂夫·凯领导的研究小组借助萤火虫的发光基因，成功地解决了这一难题。 该研究小组把萤火虫的发光基因作为标记基因，使之与一种叫拟南芥的植物的调控光合作用基因相连。待植物萌发后，喷施一种能使萤火虫发光的化合物，结果每当拟南芥的生物钟活化光合作用的时候，幼草便可开始发光。这样就容易地检测出这种植物的光合作用节律。研究人员发现，大多数拟南芥植株的光合作用周期为24小时，但其中有些植株的光合作用的周期介于 21～28小时。通过正常植株(光合作用周期为24小时)和突变类型(周期介于21～28小时)的遗传图谱比较，他们发现拟南芥控制光合作用的生物钟基因位于第五染色体上。生物钟基因的发现，有助于科学家深入了解植物是怎样调节其生理节律的。 第一段中提到“植物生物钟”，第二段提到“植物周期行为”、“生理节律”和“异步个体”。对文中这四个概念的理解，正确的一项是( )
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About a month ago I was present on a serious occasion where I heard the reading of a will. I can remember one passage that particularly struck me. It ran something (56) this. "And I direct that $ 10,000 be (57) to old William B, whom I have wished to help for many years, (58) always put off doing so." It (59) the last words of a dying man. But the story does not (60) there. When the lawyers came to (61) out the bequest (遗赠), they discovered that old William B had (62) , too, and so the (63) deed was lost. I felt rather (64) about that. It seemed to me a most regrettable. (65) that William should not have had his $10,000 just (66) somebody kept putting (67) giving it to him. And from (68) accounts, William could have done with the (69) . But I am sure (70) there are thousands of kindly little deeds waiting to be (71) today, which are being put off (72) later. George Herbert, in praise of good intentions, (73) that "One of these days is better than (74) of those days." But I say that (75) is better than all.
(五) 美国北卡罗来纳大学的研究人员在黄鼠身上鉴别并绘制出了启动动物冬眠的两个基因，这两个基因控制合成对于冬眠至关重要的酶。 据当地媒体报道，该校马修·安德鲁博士等人在黄鼠体内找到了一种基因控制合成胰腺甘油三酯酶。这种酶能分解以脂肪酸形式储存在体内的甘油三酯，然后将之转化成作为黄鼠冬眠时能量来源的脂肪。另一种基因则控制丙酮酸盐脱氢酶、激活酶和同功酶的合成，这些在饥饿时候被激发的酶能帮助保持体内的葡萄糖储备，在冬眠开始时或即将开始前，两个基因都在黄鼠的心脏中得到了表达。 研究人员还发现，这些基因与在非冬眠动物身上找到的对等基因几乎是一致的，但它们在冬眠与非冬眠动物身上的表达不一样。胰腺甘油三酯酶仅在非冬眠哺乳动物的胰腺中得到表达，却同时出现在黄鼠的胰腺和心脏中。 科学家若能鉴别出哪些是在冬眠这类极端状态下负责保护器官、降低血糖消耗和保持肌肉性能的酶，将能开发出延长移植用人体器官“保质期”的新方法，还可研制出诱导宇航员在长期太空旅行过程中安全进入冬眠状态的方法。 下列理解不符合原文意思的一项是( )
About a month ago I was present on a serious occasion where I heard the reading of a will. I can remember one passage that particularly struck me. It ran something (56) this. "And I direct that $ 10,000 be (57) to old William B, whom I have wished to help for many years, (58) always put off doing so." It (59) the last words of a dying man. But the story does not (60) there. When the lawyers came to (61) out the bequest (遗赠), they discovered that old William B had (62) , too, and so the (63) deed was lost. I felt rather (64) about that. It seemed to me a most regrettable. (65) that William should not have had his $10,000 just (66) somebody kept putting (67) giving it to him. And from (68) accounts, William could have done with the (69) . But I am sure (70) there are thousands of kindly little deeds waiting to be (71) today, which are being put off (72) later. George Herbert, in praise of good intentions, (73) that "One of these days is better than (74) of those days." But I say that (75) is better than all.
For instance, when in a new situation, an intelligent person thinks about the situa-tion, not about himself or what might happen to him.
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