| Perhaps the most familiar plant
movement belongs to one species of mimosa called the sensitive plant. Within
seconds, it can lower its leaves and make its tiny leaflets close up like
folding chairs. This movement is thought to be initiated by electrical impulses
remarkably similar to nerve signals in animals. But without the animals’
sophisticated motion machinery, the mimosa has had to be creative in devising a
way to move. For motion, the plant depends on tiny, bulb-shaped organs located at the base of each leaf stalk and leaflet. Called pulvini, these organs hold the plant parts in place. When the mimosa is stimulated--say, by a crawling insect or a sudden change in temperature--an electrical impulse sweeps through the plant. This causes potassium and then water to be shifted from certain cells in the pulvini to others, quickly turning one side of the A. reacts to outside stimulation B. has smaller leaves than most other plants C. depends on organs called pulvini D. contains potassium and water [判断题]CR400AF动车组闸片磨耗可用钢直尺直接进行测量。
A.正确 B.错误 [判断题]柴油机启动后,接地试灯的插头插入插座,对电路没有不良影响。( )
A.正确 B.错误 [单选题]高速铁路曲线超高顺坡率一般条件下不应大于( )。
A.1/(10Vmax) B. 1/(9Vmax) C. 1/(7Vmax) D. 1/(8Vmax) [单项选择]下列哪种物质与孕期筛查唐氏综合征无关
A. μE3 B. PAPP-A C. AFP D. AKP E. HCG [单选题]车站发生一般级突发大客流时，原则上（ ）预案，站长/值班站长采取相应客流控制，加强监控，并做好信息上报。
A.A、启动 B.B、不启动 [多选题]担架分为脊柱固定板、自制担架以及( )等。
A.折叠楼梯担架 B.折叠铲式担架 C.多功能担架 D.漂浮式吊篮担架 E.帆布担架 [单项选择]下列属于我国的基础部门的是（）
A. 轻工业 B. 重工业 C. 农业 D. 服务业 [单选题]辙叉心轮缘槽标准宽度（测量位置按标准图或设计图规定）为46mm,容许误差为（ ）。
A.+6，-2mm B.+3，-1mm C.+4，-4mm D.+3，-2mm [填空题]离地球最近的行星是 ( )。
[判断题]音乐不仅仅是听觉的形式，更有丰富的表现性，这用联觉可以解释。
[单项选择]如果不考虑其他因素，当存款乘数K=4、法定存款准备金率r=5%，则超额存款准备金率e等于( )。
A. 10% B. 15% C. 20% D. 25% [单项选择]在余隙体积和入口气体压强一定时，往复式压缩机的压缩比越大，其吸、排气量（）。
A. 越大 B. 越小 C. 压缩比与吸、排气量没有关系 D. 不好说 [判断题]未经安全生产培训合格的人员，可以上岗作业。
A.正确 B.错误 [单项选择]复合包装材料的主要卫生问题是（）。
A. 复合原料（塑料薄膜、铝箱、纸） B. 粘合剂马来酸改性聚丙烯 C. 粘合剂2，4（2，6）-甲苯二异氰酸酯 D. 油墨 E. 油墨和粘合剂中的溶剂的迁移 [单选题]无缝道岔导轨.辙叉.心轨.翼轨的扣件扭矩应保持( )。
A.80~150N•m B.80~140N•m C.120~150N•m D.60~80N•m [单项选择]{{B}}Section A{{/B}}
{{B}}Directions:{{/B}}{{I}} This section is to test your ability to give proper responses. There are 5 recorded questions in it. After each question, there is a pause. The questions will be spoken two times. When you hear a question, you should decide on the correct answer from the 4 choices marked A, B, C and D given in your test paper. Then you should mark the corresponding letter on the Answer Sheet with a single line through the center.{{/I}}
A. You’re welcome. B. It doesn’t matter. C. It’s very kind of you. D. You’re all right. [多选题]
调度数据网在生产控制大区与电力调度数据网的纵向交界处，应当采取相应的(____)等防护措施。 A.加密 B.安全隔离 C.过滤 D.认证 [判断题]高瓦斯和煤与瓦斯突出矿井掘进巷道中部，甲烷传感器报警浓度、断电浓度、复电浓度分别是：≥1．0%CH4、≥1．0%CH4、＜1．0%CH4。
A.正确 B.错误 [简答题]风力发电的经济效益主要取决于哪些因素？
[报关编码]铁质镀铜的领带夹
[单项选择]创立的书院定期举行学术会讲（）
A. 朱熹白鹿洞 B. 顾宪成学海堂 C. 顾宪成东林 D. 朱熹东林 我来回答: 提交
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