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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。 以下四项是检测的四个过程,对过程叙述有误的一项是( )

A. 发光基因和调控光合作用基因相连
B. 受检植物萌发后喷施能发光的化合物
C. 生物钟活化光合作用,幼苗开始发光
D. 检测出受检植物的光合作用节律

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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.

A. exciting
B. sorry
C. faithful
D. happy

月经病包括

A. 月经的周期、经期的异常
B. 经量的异常
C. 经色、经质的异常
D. 伴随月经周期出现的症状
E. 以上都是

Passage 2Questions 6 to 10 are based on the following passage: Human needs seem endless. (78) When a hungry man gets a meal, he begins to think about an overcoat, when a manager gets a new sports car, a big house and pleasure boats dance into view. The many needs of mankind might be regarded as making up several levels. When there is money enough to satisfy one level of needs, another level appears. The first and most basic level of needs involves food. Once this level is satisfied, the second level of needs, clothing and some sort of shelter, appears. By the end of World War II, these needs were satisfied for a great majority of Americans. Then a third level appeared. It included such items as automobiles and new houses. By 1957 or 1958 this third level of needs had fairly well been satisfied. Then, in the late 1950s, a fourth level of needs appeared: the "life-enriching" level. (79) While the other levels involve physical satisfaction, that is, the feed in comfort, safety, and transportation, this level stresses mental needs for recognition, achievement, and happiness. It ineludes a variety of goods and services, many of which could be called "luxury" items. Among them are vacation trips, the best medical and dental care, and recreation. Also included here are fancy goods and the latest styles in clothing. On the fourth level, a lot of money is spent on services, while on the first three levels more is spent on goods. Will consumers raise their sights to a fifth level of needs as their income increases, or will they continue to demand luxuries and personal services on the fourth level A fifth level would probably involve needs that can be achieved best by community action. Consumers may be spending more on taxes to pay for government action against disease, ignorance, crime, and prejudice. After filling our stomachs, our clothes closets, our garages, our teeth, and our minds, we now may seek to ensure the health, safety, and leisure to enjoy more fully the good things on the first four levels. Which of the following is NOT related to "physical satisfaction"

A successful career.
B. A comfortable home.
C. A good meal.
D. A family ear.

本部分着重考查考生对语言文字的理解和驾驭能力。这种能力包括:对词和句子一般意思和特定意义的理解;对比较复杂的概念和观点的准确理解;对语句隐含信息的合理推断;根据上下文,恰当选用词语;准确地辨明句意,筛选信息。注意:问题可能是选择一个词语或一个句子,使表达最为准确,也可能是考查对文字内容的理解,你的选择应与题目要求最相符合。(一) 大气中臭氧层的破坏。温室气体的增加,地球上生物多样性的减少,以及水土流失和污染的加剧都带来了严重的环境问题。保护环境,改良生态,控制气候变化是科学研究的前沿问题。全球变化,是指环境被破坏后对全球的影响。例如,温室气体的增加可以引起温度上升,会带来全球气候的变化。而地球上生物多样性的减少也是全球性的问题。前不久做过一个实验,在冰岛有很纯净的冰雪层,是若干年前积累起来的。在其中可以找到当时的气候资料,如大气的二氧化碳有多少,当时的温度是多少,从中可以看出15万年前到现在二氧化碳及温度的分布。这里有一张图片,可以看出宏观上二者大体相应的情况,说明温室气体的产生对全球气候有一定影响,但它们也不完全是对应的。最近,地球上的温度波动很厉害,二氧化碳一直在上升。但全球的温度也不是完全由二氧化碳所决定的。有很多因素有待现代科学家的研究。另外.从历史上看,自然也会影响二氧化碳的增加或减少。现在的变化是否完全是由于人为产生的温室气体,还需要进一步研究。值得注意的是,有人企图用这个来限制发展中国家能源增加,借此来抑制发展中国家的发展。这既是科学问题,可能也是政治上的问题。我们不能在科学尚没弄清之前,就轻易地作出结论。 下列说法符合原文意思的一组是( ) ①二氧化碳是温室气体,②地球温度指的就是全球气候,③全球气候变化是全球变化的一个方面,④温室气体增加可造成环境破坏,⑤二氧化碳的增加是由能源增加引起的

A. ①④⑤
B. ②③④
C. ②③⑤
D. ①③④

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