题干

下列关于植物组织培养的叙述中,错误的是(  )。

A:培养基中添加蔗糖的目的是提供营养和调节渗透压

B:培养基中的生长素和细胞分裂素影响愈伤组织的生长和分化

C:离体器官、组织或细胞都必须通过脱分化才能形成愈伤组织

D:同一株绿色开花植物不同部位的细胞经培养获得的愈伤组织基因相同

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D

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    If you ever visit an English village, make sure to look out for morris dancing. Undoubtedly one of the strangest traditions of English culture, morris dancing is a form of folk dancing that dates back to the 15th century. If you ever get the opportunely, you really have to see it.

    Men and women wearing old-fashioned, shabby clothing dance in the streets of towns and villages across the country during the holiday periods. Women wear long, frilly(有褶皱边的) skirts and men wear short trousers with bells attached to them. They dance to traditional folk music which is often played on traditional musical instruments.

    Some groups carry heavy black sticks which they beat against each other while they dance. Other groups wave handkerchiefs in the air while they perform. The dances are usually performed near a pub so that when it's over, the dancers and audience can sing some traditional folk songs over a pint of beer. The celebrations will often continue long into the night, by which point most people are too drunk to think about performing again.

    Morris dancing is a great English tradition but it's facing a big crisis. As the years go by, fewer and fewer young people are joining morris dancing groups. The dancers are getting older and older and eventually, if nothing is done to change this trends, the tradition will die out within the next few decades.

    If you've ever had the fortune to see morris dancing, you may understand why teenagers aren't rushing to sign up. Putting it to the point, it's not exactly the coolest thing for an 18-year-old to be doing. Why dress up in bells and funny costumes when you could be going clubbing? Or playing sport? Or doing anything else?

    However, it would be a great shame to lose such a fun and lively part of England's history and culture. It's important to look after some traditions and customs especially when it's something as harmless and happy as morris dancing. So here's a toast to the next generation of would-be morris dancers! Let's hope they don't leave it too late.