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

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• 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
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