在生产实践中，人们经常利用_________和_________等无性生殖的方式来栽培农作物和园林植物。-八年级生物

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• 下图为嫁接过程示意图，结构A的名称是，在嫁接时要用麻绳或塑料条捆紧扎好，目的是使接穗与砧木的紧密结合。-八年级生物
• 下列生产实践方法，不属于无性生殖的是[]A．将甘薯培养在潮湿、温暖的环境中，会长出许多幼苗，然后再将幼苗移栽。B．在秋海棠的叶背面的叶脉上划一些切口，放在湿润的土面上培-八年级生物
• 据报道，溆浦有一女青年发现自家一株桃树上有一枝条上所结的桃又大又甜，且成熟期早，写信向“杂交水稻之父”袁隆平请教如何保留这一新桃种，袁隆平教给这位女青年的技术，你认-八年级生物
• 植物的组织培养是利用____________的原理，使植物组织在人工控制的条件下，通过细胞的___________和__________，快速发育成新植株的高新技术手段。-八年级生物
• 国庆举办“菊展”时发现，有些菊花植株单株上可开出多种颜色的花朵，它的培育过程是通过[]A．有性生殖B．嫁接C．诱导变异D．扦插-八年级生物
• 青岛市十梅庵风景区内梅花品种众多、色彩艳丽，其中一种由技术人员培育的三角梅能开出红、白、紫等各种颜色的花朵。他们采用的方法应该是[]A．种子繁殖B．植物组织培养C．扦插D-八年级生物
• 一同学想在家里植栽菊花，为了保持菊花的优良品种，他应取的器官是[]A．一段枝条B．一粒种子C．一个果实D．一片叶子-八年级生物
• 晓莉同学将一株单色的野菊花，培育成具有多种颜色、多个花朵的“塔菊”，她采用了下列哪项技术[]A．种子繁殖B．扦插C．嫁接D．压条-八年级生物
• 欲使一株月季上开出几种颜色的花，应采用[]A．嫁接B．压条C．扦插D．播种-八年级生物
• 嫁接就是把一个植物体的芽或枝，接在另一个植物体上，使结合在一起的两部分长成一个完整的植物体。嫁接时应当使接穗与砧木的______紧密结合，以确保接穗成活。嫁接的步骤示意-八年级生物
• 人们常用扦插、嫁接等方法繁殖果树，同有性生殖相比，其主要优点是[]A．后代具有更强的生活力B．每代每年可提前结果C．增加后代变异性D．后代保持亲本性状-八年级生物
• 一棵苹果树上能结出“国光”、“红富士”等不同品种的苹果，采用的处理技术是[]A．扦插B．嫁接C．压条D．播种-八年级生物
• 利用兰花的一段茎尖，能在一年内生产出上百万株兰花幼苗的方法是[]A．植物组织培养B．嫁接C．出芽生殖D．分裂生殖-八年级生物
• 下图是组织培养流程图，据图回答：(1)假设A瓶内是某木本植物的一段茎尖，经过组织培养，长成了一株植物，这段茎尖可称为_________，进行组织培养的理论依据是____。(2)培养时-八年级生物
• 人工培养基中含有植物生长发育需要的各种_________、____以及一定种类和浓度的植物生长____。-八年级生物
• 关于组织培养的优点叙述不正确的是[]A．培育植物新品种B．防止植物病毒的危害C．创造新物种D．短时间内大量繁殖植物-八年级生物
• 嫁接后的植物一般保持哪种植物的优良性状[]A．接穗B．砧木C．二者的综合性状D．与二者性状无关-八年级生物
• 请结合农业生产实际，解答下列问题：（1）菊花既能进行无性生殖，又能进行有性生殖，如果要保持菊花的优良特性，易用______来繁殖；如果想培育新品种的菊花，多采用_______生殖-八年级生物
• 现有甲、乙、丙三个品种的苹果，将甲（接穗）嫁接到乙（砧木）上，接穗成活后，再用丙对其授粉，得到的苹果可食部分的性状相似于[]A．甲B．乙C．丙D．甲和丙-八年级生物
• 下图是对苹果树操作步骤示意图，分析回答（1）图中操作步骤是在生产实践中常见的营养繁殖方式，称作_______。（2）①②分别称为___________________。①与②结合时应当使①与②的___
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