题干

草莓病毒病可使草莓减产30—80%。培养和应用脱毒苗是改善草莓品质、提高产量的有效途径。科学家为获得草莓脱毒苗进行实验,选择草莓植株的不同部位,经过不同条件处理后进行组织培养,统计脱毒率如下表所示。下列有关叙述正确的是(    )

组别

培养部位

处理

脱毒率

1

盆栽草莓

38℃处理90天

66%

2

3mm茎尖

25℃处理90天

20%

3

3mm茎尖

35℃处理21天

20%

4

3mm茎尖

38℃处理14天

20%

5

3mm茎尖

38℃处理21天

60%

6

0.3mm茎尖

38℃处理28天

73-96%

7

0.3mm茎尖

38%处理46天

100%

A:茎尖切段越小,培养基需添加生长素越多

B:继续提高处理温度可更早获得脱毒苗

C:热处理与茎尖培养相结合脱毒效果更好

D:热处理脱毒法更能有效提高草莓产量

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C

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    Differences are important and they should be respected. For example, many important people throughout history were considered different, such as Thomas Edison, Albert Einstein and Abraham Lincoln. They did great things, but some people thought they were strange because they had strong feelings about something. I can understand these people because I've been in that situation before many times.

    It all started in elementary school when I realized that I wasn't like everyone else. My mom says that I have a tendency to be obsessed(着迷)with certain subjects. Unfortunately, these subjects don't interest other kids of my age and they really don't interest my teachers. In fact, my kindergarten teacher said she would scream if I mentioned snakes or lizards one more time while she was teaching the days of the week. I would get into trouble for not paying attention and the teasing began.

    In the third grade, my teacher informed me that I have Asperger's Syndrome(症状). I said, “So what? Do you know that Godzilla's suit weighs 188 pounds?”

    Later, I asked my mom, “What's Asperger's Syndrome? Am I gonna die?” She said that it's like having blinders on, and that I can only see one thing at a time, and that it's hard to focus on other things.

    People also make fun of me for knowing facts about volcanoes, whales, tornadoes and many other scientific things. My mom says that she has been able to answer many questions on Jeopardy! just by listening to what I have to say, but I've even been laughed at for being smart.

    Maybe someday I'll become a gene engineer and create the real Godzilla. I can dream, Can't I?