Although we haven't got accurate statistics, it is estimated that ______ 300 factories in this

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• I haven't seen Ann for ____ long that I've forgotten what she looks like.[ ]A. suchB. very
• These plants are watered___________.[ ]A. each other day B. every other dayC. each of two days D. ev
• Fortunately somebody happened to be passing by and called the fire department ___ the fire broke out
• Learning a foreign language can help you to understand other cultures. _____, it can be a useful ski
• ______, the fire wasn't discovered after it had started. [ ]A. Happily B. Fortunately C. Quickl
• I'm certain Davel's told you his business troubles. _____, it's no secret that he owe
• Tonny's parents thought he was at school, but ______ he was in an Internet bar. [ ]A. actually
• — Peter! How are you getting on with your studies?—Well, my grades have gone down, not too much, but
• There was no news; ____, she didn't give up hope. [ ]A. moreoverB. besidesC. but D. nevertheles
• —______, he got a low mark in the exam.— He _______. [ ]A. He is stupid; never studies hardB. Stupid
• The house rent is expensive. I've got about half the space I had at home and I'm paying___
• I'm certain Davel's told you his business troubles. _____, it's no secret that he owe
• The old man came to our restaurant so ____ that all of us were familiar with him. [ ]A. frequentlyB.
• The questionnaire takes _____ten to fifteen minutes to complete and can be used along with the asses
• — The film is, I have to say, not a bit interesting. — Why? It's _____ than the films I have ev
• The policemen _____ the murderer. [ ]A. are still searching B. are searching stillC. still search D.
• People who exercise _____ are less likely to feel stress. [ ]A. regularly B. formally C. mostly D. p
• Mother went shopping; _____, I cleaned the house. [ ]A. while B. whenC. however D. meanwhile -高二英语
• These flowers should not be watered too _____, once _____. [ ]A. long; every other day B. often; eve
• — Do you think it's a good idea to make friends with my students? — _____, I do. I think it
• His father told me that he _____ for the United States three days _____.[ ]A. has left; ago B. had l
• 人们常剪取一段花卉的枝条插到土壤中进行繁殖，该繁殖方法是[]A．嫁接B．扦插C．压条D．种子繁殖-八年级生物
• 关于植物组织培养，下列不正确的叙述是[]A．植物组织培养是在人工控制的条件下，经过细胞分裂、分化，快速发育成新植株的高新技术手段B．利用植物组织培养技术能在短期内培养出-八年级生物
• 用“金帅”苹果的主干做砧木，用“红富士”苹果的枝条做接穗，进行嫁接，结出的苹果是___________苹果。-八年级生物
• 从“有心栽花花不成，无心插柳柳成荫”的诗句中，可知柳树可以采用的繁殖方式是[]A．嫁接B．扦插C．地下茎繁殖D．组织培养-八年级生物
• 要使一种开白花的植株上同时开出白花、红花、紫花，采用的方法是[]A．组织培养B．播种C．扦插D．嫁接-八年级生物
• 非洲凤仙花可利用种子或扦插繁殖，表中哪个选项正确[]A．种子繁殖：需经精卵结合扦插繁殖：不需要精卵结合B．种子繁殖：需经细胞分裂扦插繁殖：不需经细胞分裂C．种子繁殖：属于无性-八年级生物
• 在嫁接植物时，一定要注意将[]A．木质部接上B．形成层接紧C．韧皮部接紧D．树皮接在一起-八年级生物
• 下列哪项不是组织培养的优点[]A．可以促进植物开花结果B．可以用来培养新的植物品种C．可以防止植物病毒危害D．可以短时间内大量繁殖植物-八年级生物
• 有位同学在进行嫁接实验中，将蟹爪兰嫁接在仙人掌上，那么将来形成的植株开的花是[]A．仙人掌的花B．蟹爪兰的花C．不会开花D．结合两种植物特点的花-八年级生物
• 观察下图，回答问题。(1)植物的嫁接有枝接和芽接的方式，A属于___________，B属于____。(2)A图的①是___________，②是___________；B图的①是__________
• 推广使用乙醇汽油可以减轻污染、缓解能源紧张，所使用的燃料乙醇是以非粮作物木薯为原料生产的。在农业生产中木薯的繁殖方式是[]A．有性生殖B．扦插C．种子繁殖D．嫁接-八年级生物
• “有心栽花花不开，无心插柳柳成荫”，“插柳”采取的方法是[]A．嫁接B．分根C．扦插D．杂交-八年级生物
• 某果园的苹果树大都产量较低、果实品质欠佳。若要尽快更新优质苹果树，你的合理化建议是[]A．种子繁殖B．全部换栽C．果枝扦插D．果枝嫁接-八年级生物
• 利用植物组织培养的方法，只需要用少量植物材料，就可以在短期内诱导出大量试管苗。[]-八年级生物
• 看图填空（1）图中操作步骤是在生产实践中常见的_______方式，属于_____生殖。（2）图一所指的是______，图二所指的是______。两者的区别是图一是用______做接穗，图二是用____
• 植物嫁接的基本方法和原理嫁接时要使_______和_______的_________紧密结合在一起，这样才能使两部分细胞愈合在一起，提高成活率。嫁接后的植株往往具有_______特征。嫁接有_-八年级
• 在进行嫁接时，接穗和砧木的要紧密结合，以保成活。-八年级生物
• 梨、桃等果树常用播种的方法来繁殖。[]-八年级生物
• 对于月季、杨、柳等容易生根的植物，一般用嫁接的方法来繁殖。[]-八年级生物
• 园艺师能将一株仙人掌培育成具有多种性状、开多种颜色花朵的仙人掌类植物，能达到上述目的的技术是[]A．组织培养B．嫁接C．种子繁殖D．扦插-八年级生物
• 某果园的苹果树大都产量较低、果实品质欠佳。若要尽快更新为优质苹果树，你认为最快捷的做法是[]A．利用种子繁殖B．全部换栽C．进行果枝扦插D．进行果枝嫁接-八年级生物
• 鸭梨味道香甜，但适应性差；野生梨味酸，但适应性强。将鸭梨的枝条嫁接到野生梨的砧木上，该枝条成活后所结果实的味道[]A．与鸭梨一样香甜B．与野生梨一样酸C．介于鸭梨和野生梨-八年级生物
• 如图所示：（1）①是________。②是_________。（2）这种生殖方法叫_________，属于________（有性或无性）生殖，因为：_____________________。-八年级
• “有心栽花花不活，无心插柳柳成荫”说明繁育柳树容易成活的方式是-八年级生物
• 嫁接中，接上去的芽或枝叫做________，被接的植物叫做________，嫁接时应使__________才能使其成活。-八年级生物
• 农业生产中，常见的无性生殖方式有_________、_________等。-八年级生物
• 在学习了绿色植物的相关知识后，兴趣小组对豌豆的生长过程进行了探究，如下图所示。请据图回答问题：（1）选种时，该小组同学对豌豆种子的结构进行了观察，发现胚是由胚芽、胚轴-八年级生物
• 人工营养生殖的常用方法有：___________、___________和________等。-八年级生物
• 人们获得“人工种子”所利用的生物技术是[]A．转基因技术B．组织培养技术C．动物克隆技术D．嫁接技术-八年级生物