题干

科学家发现一种叫“熊虫”的动物,能耐受零下271℃的冰冻数小时(这时它的代谢率几乎降至0).此时,它们的体内会大量产生一种叫做海藻糖的二糖.实验证明该动物体液中的海藻糖可以使组织细胞避免因低温而造成的损伤.

请回答下列问题:

(一)对于“熊虫”种群而言,具有产生大量海藻糖,耐受低温这种特征是____ 的结果;对“熊虫”个体而言,具有这种特征的根本原因是____ 

(二)为探究海藻糖对普通哺乳动物组织细胞是否也具有上述保护作用,某生物兴趣小组设计了如下实验,请将其补充完整.

(1)实验材料:

①海藻糖;

②细胞培养液及其他相关材料;

③适量哺乳动物细胞.

为了确保实验的科学性和准确性,从化学组成及生理功能看,该细胞应具有____的特点.

(2)操作过程:

①取适量哺乳动物细胞,等分成甲、乙两组(以甲组为实验组),向甲组细胞中添加____ ,向乙组细胞中添加____

②____  .

③观察并记录两组细胞的生活状况.

(3)预期结果及相应结论:

该实验结果会有____  种可能性,如果实验结果是____,则说明该海藻糖在低温下对普通哺乳动物组织细胞具有保护作用.

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同类题1

阅读理解Answer the questions

    You are invited to a large party. Loud music is playing, and lots of people are dancing. Do you dance or talk to as many people as you can call all night? Later, you cannot fall asleep—you want more conversation! Or do you prefer a quieter corner? Or perhaps you cannot wait to go home early and relax by yourself.

    Which of these people sound most like you? Person A, who tries to talk to everyone and stays late? Or Person B, who prefers to keep quiet and leaves early?

    If you said Person A, you are probably more extroverted(性格外向的). If you said Person B, you are probably more introverted(内向的). Or perhaps you are Person C and fall somewhere in the middle. Introverted and extroverted people are two commonly used words to describe a person's personality. And they are also commonly misused and misunderstood.

    Introverts may be thought as quiet, shy and timid. Extroverts may be thought as bold, confident, loud and full of energy. Introverted and extroverted people may fit those descriptions. But these same descriptions do not define(下定义)introversion and extroversion properly.

    Introverts and extroverts use their brains differently, and they get their energy differently. Introversion is the state of being mostly concerned with one's own mental life. Extroversion is the opposite. Extroversion is the state of being mostly concerned with what is outside oneself.

    People who consider themselves introverts may say they “need to be alone to charge their batteries”. However, introverts may still live being social and going to parties. But such activities require time to prepare.

    Extroverts may say, “I don't need ‘alone time', I feel more relaxed being around other people.” Even so, extroverts can still feel unsure or not confident among other people.

    So where do you fall on the introversion/ extroversion chart?