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

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• 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
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• 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
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