题干

某生物小组为了探究甲状腺激素对蝌蚪发育的影响,设计如下实验步骤:

a.取三个玻璃缸编号为甲、乙、丙,各加入500ml池塘水和等量的蝌蚪饲料;

b.在三缸中加入同时孵化的相同数量的蝌蚪(不少于5只),保持水温22﹣25℃;

c.处理方式和实验结果如下表:

组别

处理方法

不做任何处理

破坏蝌蚪甲状腺

水中加入甲状腺激素

实验结果

正常发育成青蛙

停止发育

提前发育成苍蝇般大小的青蛙


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    Perhaps you think you could easily add to your happiness with more money. Strange as it may seem, if you're unsatisfied, the issue is not a lack of means to meet your desires but a lack of desires—not that you cannot satisfy your tastes but that you don't have enough tastes.

    Real riches consist of well-developed and hearty capacities (能力) to enjoy life. Most people are already swamped (淹没) with things. They eat, wear, go and talk too much. They live in too big a house with too many rooms, yet their house of life is a hut(草棚).Your house of life ought to be a mansion (豪宅), a royal palace. Every new taste, every additional interest, every fresh enthusiasm adds a room. Here are several rooms your house of life should have.

    Art should be a desire for you to develop simply because the world is full of beautiful things. If you only understood how to enjoy them and feed your spirit on them, they would make you as happy as to find plenty of ham and eggs when you're hungry.

    Literature, classic literature, is a beautiful, richly furnished room where you might find many an hour of rest and refreshment. To gain that love would go toward making you a rich person, for a rich person is not someone who has a library but who likes a library.

    Music like Mozart's and Bach's shouldn't be absent. Real riches are of the spirit. And when you've brought that spirit up to where classical music feeds it and makes you a little drunk, you have increased your thrills(excitement) and bettered them. And life is a matter of thrills.

    Sports, without which you remain poor, mean a lot in life. No matter who you are, you would be more human, and your house of life would be better supported against the bad days, if you could, and did, play a bit.

    Whatever rooms you might add to your house of life, the secret of enjoying life is to keep adding.