题干

我国植物学家将“蓝色妖姬”(一种玫瑰)的茎尖细胞放在培养基中进行培养,最终发育成完整的新植株.

(1)过程③和④分别表示________ .

(2)在培养过程中,除了提供水分、无机盐、糖类、维生素及氨基酸外,还需要在培养基中加入____

(3)从育种的角度看,植物组织培养与有性生殖相比,优势主要有(请列举两点)____ 、____ .

(4)在植物组织培养的过程中,可以对____ 进行化学或物理的诱变处理,促使其发生突变,再通过诱导分化形成植株,从中选育出优良品种,这种作物新品种的培育方法属于诱变育种.

(5)若将玫瑰的茎尖细胞换成玫瑰的花粉粒经组织培养形成植株,染色体加倍后当年便可得到稳定遗传的优良品种,这种育种方法称为____ ,其优点是____

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\u8131\u5206\u5316,\u518d\u5206\u5316,\u690d\u7269\u6fc0\u7d20,\u80fd\u4fdd\u6301\u4eb2\u672c\u7684\u4f18\u826f\u6027\u72b6,\u80fd\u5927\u91cf\u5feb\u901f\u7e41\u6b96,\u6108\u4f24\u7ec4\u7ec7,\u5355\u500d\u4f53\u80b2\u79cd,\u80fd\u660e\u66

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    A cab company in one of Japan's major cities is introducing silent taxi drivers. Miyako Taxi, which is based in Kyoto, shows the new idea in March. The business is currently operating five “Silence Taxis” across the city.

    The cars look like any ordinary taxi,but a notice written on the back of the passenger seat  inform passengers that they have entered one of the new silent fleet. Drivers will offer a greeting when their passenger enters the car, and aside from confirming the route they will not engage in small talk. The drivers can indulge in conversation, only if they are spoken to first, and they are also allowed to communicate in emergency situations.

    Announcing the idea, Miyako Taxi said: “This service is currently in a trial stage, with the goal of creating an in-car atmosphere that provides the most comfortable ride for passengers through limiting the driver's speaking.” According to Japan Today, they made the move after hearing reports from passengers that they were fed up being forced to chat with their drivers.

    The company will assess the popularity of the trial before deciding whether to expand it and roll it out across more of their drivers.

    Language and speaking is at the heart of another issue facing Uber drivers, after lost a High Court Battle to block written tests in London. Drivers applying for a minicab license in the capital will now have to pass the written exam following Uber's failed challenge against Transport for London (TfL). The company argued it could see up to 33,000 existing drivers lose their licences under the new rule.

    The company's London head, Tom Elvidge: vowed to challenge the rule and said, “We've always supported spoken English skills, but writing an essay has nothing to do with communicating with passengers or getting them safely from A to B.”