题干

在一对相对性状的杂交实验中,下列有关性状分离现象的假设,错误的是  (    )

A:生物的性状是由细胞中的遗传因子决定的

B:体细胞中的遗传因子成对存在

C:在配子中只含有每对遗传因子中的一个

D:生物的雌雄配子数量相等,且随机结合

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D

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    When I spent the summer with my grandmother, she sent me down to the 1with a list, I walked up to the counter.Behind it was an old lady named Miss Bee.
    “Excuse me,”I said. She 2“I need to get these,”I continued, 3up my list.
    “So? Go get them,”Miss Bee said.“4is here except you and me, and I'm not your servant. I suggest you get yourself a basket over there and start5.”It was not 6for a 7­ year ­old child, there were so many different kinds of things. I spent over an hour in the store.
I visited Miss Bee twice a week that summer. She 7short­changed me. Other times she overcharged. Going to the store was like going into a war. But by the end of that summer, I could finish my shopping trip8around 15 minutes. The morning I was to return home, I stopped in the store again to buy something.
    “All right,”Miss Bee said. “What did you 9this summer?”
    “That you're mean!”I replied.
    Miss Bee just laughed,“ I know 10you think of me,”she said. “Well, I don't care! My job is to teach every child I meet some life 11. When you get older you'll be glad that you met me!”Glad I met Miss Bee? Ha!How could it be?
    It sounded funny until one day my son came to me with his homework. “It's too 12 . ”he said. “Could you finish the math problem for me?”
    “13I do it for you, how will you ever learn to do it  yourself?”I said. Suddenly, I was back in that store where I had learned to add up my bill by myself. Had I ever been overcharged since?
    Life is full of all kinds of 14. We may be 15 a hand once or twice, but luck may not find us every time. So we should work them out by ourselves.