题干

在生物实验中,有些实验材料用品是可以替代的。下列做法合理的是:

A:观察植物细胞有丝分裂实验中,用小麦根尖代替洋葱根尖

B:做可溶性还原糖鉴定的实验时,用西瓜代替梨

C:做叶绿体中色素的提取实验时,可用水代替酒精

D:做DNA粗提取实验时,用猪血代替鸡血

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A

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    Being a sports reporter for more than a decade, I see “Olympic” as a1word to me. I found the word is also a(an)2for everyone to shine. This feeling3me when I was holding the Olympic torch for the4time on Monday in Seoul, the capital city of South Korea.

    I felt such a great5to be invited by the International Olympic Committee to be a torchbearer for the 2018 Pyeongchang Winter Games 6Chinese sports reporters. Ten years ago, I was invited by IOC to be a7for the 2008 Beijing Summer Games. I have now carried the torch in two different countries. I have 8how the Olympic flame 9everybody around it.

    When I arrived at the 10point for the torchbearers, all the staff and even passers-by cheered because they knew I would be joining the11. I could feel their heartfelt12 toward the Olympics. When a group of torchbearers left to join in the relay, all the people13 shouting “Fighting!” While I14my turn, many people came to take photos with me and the torch. In 101 days, the route15nine provinces and eight major cities across the country. With less than a month to go before the Games1 opening ceremonies in Pyeongchang, Seoul had been16 into an Olympic city as well.

    “Let everyone shine' is not just a slogan for the torch relay but 17the fact that ordinary people from every walk of life—students, bakers, teachers, farmer —are18.The Olympic spirit is a lot more than the19 of 'swifter, higher, and stronger.' 'Olympic, has the magic to bring everyone together to20their dreams.