苎麻俗称“中国草”，苎麻纤维所制纺织品具有挺括凉爽、易洗快干、牢固舒适等特点，颇受国内外消费者青睐．

（1）苎麻的β﹣葡糖基转移酶能催化纤维素合成，该酶能提高反应速率的机理是____ 

（2）图1表示在适宜的光照、CO₂浓度等条件下，苎麻在不同温度条件下的净光合作用速率和呼吸作用速率曲线．

①光合作用和呼吸作用都受温度的影响，其中与____ 作用有关的酶的最适温度更高．

②光合速率与呼吸速率相等时对应的温度是____  ℃．在温度为40℃的条件下，该苎麻叶肉细胞叶绿体利用的CO₂来源是____ 

③若温度保持在20℃的条件下，长时间每天交替进行12h光照、12h黑暗，该苎麻能否正常生长？，原因是____ 

（3）为解决苎麻纤维颜色单一的问题，科研人员利用基因工程对苎麻进行了改良，其基本流程如图2．请分析回答下列问题：

①构建重组质粒时，需要用到____ 酶，质粒的③端会和切出的目的基因的端____  （填①或②）相连接

②苎麻茎尖细胞通过____  （填生物技术名称）获得完整植株的过程，有力的证明了及时高度分化的细胞仍具有____性．

David was so excited at the good news that he could      say a word．  

    "Depend on yourself" is what nature says to every man. Parents can help you. Teachers can help you. Others still can help you. But all these people only help you to help yourself.

    There have been many great men in history. Many of them were very poor when they were young, and had no uncles, aunts, or friends to help them. Schools were few and not very good. They could not depend on them for education. They tried their best to learn something and never gave up till they became well-known. One of the most famous teachers in England used to tell his pupils, "I cannot make worthy men of you, but I can help you make men of yourselves."

    Some young men don't try their best to make themselves valuable to the human beings. If they see their weak points and change their ways, they can be successful. They are nothing now, and will be nothing as long as(只要) they live, unless they accept the advice of their parents and teachers, and depend on themselves.

假如古人评论说“隋炀帝此举，为其国促数年之祚（国运），而为后世开万世之利，可谓不仁而有功。”隋炀帝开凿大运河的“功”是（　　）