13. Which of these external stimuli produces a growth of the plant toward light? A, negative gravitropism B, positive gravitropism C, negative phototropism D, positive phototropism 14, Which of these stimuli causes a pea vine to twine around a wire support? A、 thigmotropism B、 negative gravitropism C, positive gravitropism D, positive phototropism 15. How does auxin actually work? A, In the presence of light, it increases the turgor pressure of the cell and accelerates growth B, In the presence of light it increases the formation of hydrolytic enzymes that release energy needed for gronth purposes C, In the presence of light, it moves toward the light source and activates a protein that binds to DNa and starts enzyme production D, In the presence of unidirectional light, it moves to the shady side and activates and h ATPase that results in weakened(fa t)cell walls and eventual elongation 16. The function of endosperm isto A、 develop in the fruit B、 form the seedling C, provide water to the em D provide nutrients to embry 17. When flower meristems used to clone plants, embryolike structure called form at the top of the callus C、 phytochromes D、 somatIc(体细胞) embryos 六、填空题( Put the best word in the blanks) 1、种子萌发必须有适当的外界条件,即 或 2、种子萌发时,淀粉会被淀粉酶、脱支酶和麦芽糖酶等水解为 3、种子萌发时,脂肪在脂肪酶的作用下,水解生成 和 。蛋白质 在蛋白酶和肽酶的作用下生成 4、控制茎生长最重要的组织是 5、植物体的一部分对其他部分生长发育的调节作用称为 6、光之所以抑制多种作物根的生长,是因为光促进了根内形成 的缘故。 7、植物随光的方向而弯曲的能力,称为 8、有生活力的种子,遇到TTC后,其胚呈色 9、植物组织培养的理论依据是 10、土壤缺氮时,使根冠比值 七、问答题( Answer the following question) 1、种子的萌发必需的外界条件有哪些?种子萌发时吸水可分为哪三个阶段?第一 阶段细胞靠什么方式吸水? 2、常言道:“根深叶茂”是何道理? 3、高山上的树木为什么比平地生长的矮小? 4、什么叫植物的向光性?向光性生长的机理如何?13、Which of these external stimuli produces a growth of the plant toward light ? A、negative gravitropism B、positive gravitropism C、negative phototropism D、positive phototropism 14、Which of these stimuli causes a pea vine to twine around a wire support? A、thigmotropism B、negative gravitropism C、positive gravitropism D、positive phototropism 15、How does auxin actually work? A、In the presence of light, it increases the turgor pressure of the cell and accelerates growth. B、In the presence of light, it increases the formation of hydrolytic enzymes that release energy needed for gronth purposes. C、In the presence of light, it moves toward the light source and activates a protein that binds to DNA and starts enzyme production. D、In the presence of unidirectional light, it moves to the shady side and activates and H+— ATPase that results in weakened(松驰) cell walls and eventual elongation 16、The function of endosperm isto A、develop in the fruit B、form the seedling C、provide water to the embryo D、provide nutrients to embryo 17 、 When flower meristemis used to clone plants, embryolike structure called _____________form at the top of the callus A、particle guns B、protoplast C、phytochromes D、somatic(体细胞) embryos 六、填空题(Put the best word in the blanks) 1、种 子萌发 必须有 适当 的外界 条件， 即_______________ 、______________、 _____________或_____________。 2、种子萌发时，淀粉会被淀粉酶、脱支酶和麦芽糖酶等水解为____________。 3、种子萌发时，脂肪在脂肪酶的作用下，水解生成__________和___________。蛋白质 在蛋白酶和肽酶的作用下生成__________。 4、控制茎生长最重要的组织是_____________和_______________。 5、植物体的一部分对其他部分生长发育的调节作用称为 __________。 6、光之所以抑制多种作物根的生长，是因为光促进了根内形成_______的缘故。 7、植物随光的方向而弯曲的能力，称为___________。 8、有生活力的种子，遇到 TTC 后，其胚呈_____色。 9、植物组织培养的理论依据是____________。 10、土壤缺氮时，使根冠比值_______。 七、问答题(Answer the following question) 1、种子的萌发必需的外界条件有哪些？种子萌发时吸水可分为哪三个阶段？第一、三 阶段细胞靠什么方式吸水？ 2、 常言道：“根深叶茂”是何道理？ 3、 高山上的树木为什么比平地生长的矮小？ 4、什么叫植物的向光性？向光性生长的机理如何？