题干

玉米(2N=20)果皮黄色(A)对白色(a)为显性,非甜味(B)对甜味(b)为显性,非糯性(G)对糯性(g)为显性,三对基因分别位于三对同源染色体上.现有甲、乙、丙、丁四个品系的纯种玉米,其基因型如表所示:

品系

基因型

AABBGG

aaBBGG

AAbbGG

AABBgg

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Dear Reader,
    Imagine an 11-year old girl whose days are often spent washing clothes, looking after a baby, working hard in the field.
    Imagine a little girl who knows there will not be enough food for dinner, who can't fill her stomach with water because it's polluted, and who has watched life slip away from her father, little brother and sister because the family is too poor to see a doctor.
    Is it hard to believe? For Maria Pastora, these are the real life.
    Maria would gladly walk miles to school, but her mother, now alone, needs her badly at home. If Maria grows up without any schooling, what will be her future?
    But for just 52 pennies a day, you can sponsor a child like Maria. Through “Save the Children”, you can help Maria’s mother get the tools and ways she needs to turn their poor food into a good dinner and the money she needs to buy clothes and school things for Maria.
To help Maria most, your money is put together with that of other sponsors, so hard-working people can help themselves. Build a school, a hospital…bring in clean water. This is what “Save the Children” has been about since 1932.
    For you there are many rewards. Have the chance to write to or hear from your sponsored child. Receive photos or progress reports. Know you are reaching out to another person. Not with a handout(施舍物), but a “handup”. That's how “Save the Children” works. But without you, it can't work. Please take a moment now to fill in and post the form below to help a child like Maria and her village.
It can make such a difference in her life and yours.

同类题5

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    “As easy as falling off a log” is often used to describe a job that does not take much effort. You might hear a student say to her friend that her spelling test was “as easy as falling off a log”. ____. It is easier to fall off the log than to stay on it.

    ____. One is “easy as pie”. Nothing is easier than eating a piece of sweet, juicy pie unless it is a “piece of cake”.

    “Piece of cake” is another expression that means something is extremely easy to do. A friend might tell you that his new job was a “piece of cake”.

    Another expression is “as easy as shooting fish in a barrel”. It is hard to imagine why anyone would want to shoot fish in a barrel. But, clearly, fish in a barrel would be much easier to shoot than fish in a stream. ____.

    Sometimes, things that come to us easily, also leave us just as easily. In fact, there is an expression —“easy come, easy go”—that recognizes this. ____. Easy come, easy go.

    When life itself is easy, when you have no cares or problems, you are on “Easy Street”. Everyone wants to live on that imaginary street.

    ____. It means to treat a person kindly or gently, especially in a situation where you might be expected to be angry with him. A wife might urge her husband to “go easy on” their son, because the boy did not mean to damage the car.

A. If you ever tried to walk on a fallen tree log, you understand what the expression means.

B. You may win a lot of money in a lottery, then spend it all in a few days.

C. Every people has its own way of saying things, its own special expressions.

D. Another “easy” expression is to “go easy on a person”.

E. There are several other expressions that mean the same thing.

F. And one last expression, one that means do not worry or work too hard.

G. In fact, it would be as easy as “falling off a log”.