(单选题)27: 薄壁细胞的主要特征是 ( ) A: 死细胞 B: 具发达的胞间隙 C: 具次生壁加厚 D: 具初生壁加厚 E: 无液泡 ...
(单选题)21: 某一双子叶植物叶上的气孔,副卫细胞为两个,气孔长轴与副卫细胞长轴垂直,该气孔轴式为 ( ) A: 不定式 B: 环式 C: 不等式 D: 平轴式 E: 直轴式 ...
(单选题)15: 一般蓼科植物所含的草酸钙结晶为 ( ) A: 方晶 B: 针晶 C: 簇晶 D: 沙晶 E: 柱晶 ...
(单选题)9: 植物细胞特有的细胞器是 ( ) A: 线粒体 B: 溶酶体 C: 质体 D: 核糖体 E: 高尔基体 ...
(单选题)3: 桔梗科和菊科一些植物根中,多存在有 ( ) A: 淀粉粒 B: 菊糖 C: 橙皮甙 D: 三者均无 E: 三者均有 ...
(单选题)47: The new discoveries there have ____ greatly to our knowledge of the ancient civilization in Chin A: attached B: proceeded C: added D: contributed ...
(单选题)41: On hearing the order to search for a lost child, the policemen ______ at once. A: set out B: set aside C: set down D: set back ...
(单选题)35: Dick has ______ his childish habits. A: outdone B: outnumbered C: outlet D: outgrown ...
(单选题)23: I don't know why he is about to make a _______ over a few pounds. A: commotion B: fuss C: noise D: mess ...
(单选题)17: Peter took up the rear, armed with a large hammer _____ emergencies. A: in that case of B: in any case of C: in case of D: in the case of ...