题干

下列关于细胞全能性的叙述,正确的是(    )

A:水稻的正常体细胞及其卵细胞均具有全能性

B:细胞的全能性是指细胞具有全面的生理功能

C:玉米种子萌发长成新植株能体现细胞全能性

D:造血干细胞形成各种血细胞能体现细胞全能性

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A

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    Last winter vacation, my brother got a set of bedroom furniture for his thirteenth birthday. When it arrived, I helped my parents moved the 1  furniture to the garage(车库). It was still in good condition. I thought it might be a chance for us to2 someone in our community. I started to search neighbors, anyone who 3 a bedroom set. Finally, my mom helped me call the local primary school. They told me about Jaila, the daughter of a poor single mother. I was given a telephone number and 4 and I soon found myself at Jaila's.

    The moment I went into Jaila's room, I knew I had taken on too big a task. When I pushed the old door open, it made a long high noise. But the door was nothing compared with the rest of the room. Some old paint was 5 the wall. One of the windows was 6. The bed was just a mattress(床垫)on the old carpet. It seemed that the room needed7 furniture — it cried — for a complete makeover(翻新).

    That day I spent at least an hour looking around and 8how I could possibly fixed the room. I had never painted a wall, let alone fixed a floor. The second day, I returned with a large group of helpers — my close friends. We went to collect everything needed door to door in our community. We replaced and repainted Jaila's room. We sweated in Jaila's house for more than ten hours every day that week.

    The moment we finished, we called Jaila into the room. She jumped, laughed and hugged each of us. I turned to Jaila's mother, and saw she had tears running down her face.

    "Anna," Jaila called my name 9Yes?""Welcome to my new room!"

    When we saw how happy Jaila and her mother were, our tiredness disappeared into thin air. We are really10 to make a special experience of changing someone's life.