题干

下列据图所作的推测,错误的是(   )

A:基因型如甲图所示的两个亲本杂交产生AaBb后代的概率为1/4

B:乙图表示孟德尔所做的豌豆两对相对性状遗传实验中F2的性状分离比

C:丙图中5号女儿患单基因遗传病,那么3、4号异卵双生兄弟的基因型相同

D:丁图所示生物的细胞中很可能含有三个染色体组

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答案(点此获取答案解析)

C

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    James shook his money box again. Nothing! He carefully 1the coins that lay on the bed, $24.52 was all that he had. The bicycle he wanted was at least $90!2 on earth was he going to get the 3 of the money?

    He knew that his friends all had bicycles. It was 4to hang around with people when you were the only one without wheels. He thought about what he could do. There was no point asking his parents, for he knew they had no money to 5.

    There was only one way to get money , and that was to earn it. He would have to find a job. But who would hire him and what could he do? He decided to ask Mr. Clay for advice, who usually had 6on most things.

    "Well, you can start right here, "said Mr. Clay." My windows need cleaning and my car needs washing."

    That was the 7of James' odd-job (零工)business. For three months he worked every day after finishing his homework. He was amazed by the variety of jobs that people 8 for him to do. He took dogs and babies for walks, cleared out cupboards, and mended books. He lost count of the9of cars he washed and windows he cleaned, but the 10increased and he knew that he would soon have 11for the bicycle he wanted.

    The day finally came when James counted his money and found $94.32. He 12no time and went down to the shop to pick up the bicycle he wanted. He rode 13home, looking forward to showing his new bicycle to his friends. It had been hard 14for the money, but James knew that he valued his bicycle far more since he had bought it with his own money. He had 15what he thought was impossible, and that was worth even more than the bicycle.