热门试题:
[简答题]四显示自动闭塞区段,连续式机车信号机显示一个带“2”字的黄色灯光的含义是什么?J435
[判断题]严禁在有毒区域脱卸或更换防护装备。
A.正确
B.错误
[单选题]《铁路乘车证管理办法》规定,临时定期乘车证是职工一次出差到几条线又不顺路,可按线填最远到站,但不能超过()到站。
A.4个
B.2个
C.5个
D.3个
[判断题]若ABS系统无故障,打开点火开关3秒内指示灯灭;如果系统有故障,指示灯将常亮。( )
A.正确
B.错误
[单选题]下列哪种黏膜病变不属于癌前病变
A.白斑
B.口腔扁平苔藓
C.口腔黏膜下纤维性变
D.盘状红斑狼疮
E.着色性干皮病
[多选题]按电话命令执行的工作应留有( )或( )。
A.录音
B.电话号码
C.书面派工记录
D.发令时间
[多选题]以下属于高层公共建筑的是( )
A.建筑高度为 24m 的 6 层门诊楼
B.建筑高度为 54m 的医疗住院部
C.建筑高度为 20m 的党政机关办公楼
D.建筑高度为 48m 且 24m 以上部分每层楼层建筑面积为 1000m²的商业建筑
E.建筑高度为 25m 的 5 层商业建筑,每层建筑面积为 10000m
[判断题]露剂系指含挥发性成分的药材用水蒸气蒸馏法制成的芳香水剂,适用于芳香药物的制剂,供外用。
[判断题]凭临时道路旅客运输标志牌运营的客车应当按照正班车的线路和站点运行。( )
A.正确
B.错误
[单项选择]下述结论正确的是()。
A. 同一截面对不同轴的惯性矩、惯性积不同
B. 组合截面惯性矩不一定等于各分截面对此轴惯性矩之和
C. 惯性矩、极惯性矩永远为负
D. 惯性积永远为正
[单项选择]百货店成熟门店调整时,方案经会议确定后,品牌置换不得超出多少?()
A. 10%
B. 20%
C. 30%
D. 40%
[单选题](单选题)当电线搭落在触电者身上或压在身下时,可用( )等绝缘物作为工具,拉开触电者或挑开电线,使触电者脱离电源
A.铁棒
B.湿的绳索
C.干燥木棒
D.绝缘导线
[单选题]下列关于差额法评估收益额的计算公式中,错误的是( )。
A.收益额=销售收入×销售收入分成率×(1-所得税税率)
B.收益额=销售利润×销售利润分成率×(1-所得税税率)
C.销售收入分成率=销售利润分成率÷销售利润率
D.销售利润分成率=销售收入分成率÷销售利润率
[判断题]注射对比剂后,乳腺内各正常组织可轻度增强。
[单选题]有关牙周袋的概念,错误的是
A.牙周袋是病理性加深的龈沟
B.牙周袋包括骨上袋和骨下袋
C.假性牙周袋因牙龈肿胀或增生所致
D.真性牙周袋是指PD≥6mm的牙周袋
E.临床上的牙周袋既有龈缘向冠方延伸,也有沟底向根方延伸
[多选题]化学品及企业标识主要标明()邮编、电话、传真等信息。
A.化学品名称
B.生产企业名称
C.地址
D.应急电话
[多选题]期货公司应当在5个工作日内向其住所地的中国证监会派出机构书面报告的情形有( )。
A.变更名称. 公司章程
B.作出终止业务等重大决议
C.被有权机关立案调查或者采取强制措施
D.任免董事. 监事. 高级管理人员. 财务负责人. 营业部负责人,或者高级管理人员的分工发生变更
[单项选择]在何种条件下,飞行员在收到着陆机场低于最低着陆标准的天气预报后,可以继续仪表进近到决断高?()
A. 在雷达环境下实施仪表进近
B. 当飞行员切入航向道以后
C. 当飞行员仪表进近的最后进近阶段
[单项选择]右心衰竭引起淤血的器官主要是()。
A. 肺、肝及胃肠道
B. 肺、脑及胃肠道
C. 肝、脾及胃肠道
D. 肾、肺及胃肠道
E. 脾、肺及胃肠道
[判断题] 癫疯穴位于肱二头肌外侧缘中1/3与下1/3交界稍上方凹陷中。( )
A.正确
B.错误
[多选题]依据《安全生产法》的规定,负有安全生产监督管理职责的部门在依法对生产经营单位执行有关安全生产的法律、法规和国家标准或者行业标准的情况进行监督检查时,可以依法行使的职权有( )。
A.现场检查权
B.当场处理权
C.紧急处置权
D.查封扣押权
E.责令关闭权
[判断题]分解管系时,橡胶密封件须更换新品,橡胶密封圈须使用E型密封圈。
A.正确
B.错误
[判断题]铁路电子客票报销凭证不能办理票面置换业务。
A.正确
B.错误
[单选题]《电力电缆线路运行规程:7.2.4》 为防止电缆过负荷,对多条并列运行的电缆有检测要求。以下不属于检测内容的是()。
A.电流分配
B.电缆表面温度
C.电缆环境温度
D.电流分配和表面温度
[判断题]“回首向来萧瑟处,归去,也无风雨也无晴。”出自李清照《醉花阴•薄雾浓云》
[多选题]电子会计档案的数据信息应定期检查,必要时需转存,以确保档案信息()。
A.可靠
B.真实
C.完整
D.可读
[多选题]碎煤机控制信号主要有()
A.启动
B.停机
C.正常、旁路选择
D.振打器控制
E.检修设置
A.A
B.B
C.C
D.D
E.E
F.F
[判断题]动销率超过100%说明了在某个时段该分类的销售品项数低于目前现有库存的品项数,说明了该分类出现了品项数的流失现象。
A.正确
B.错误
[单选题]臂丛内侧束发出的神经是;( )
A.尺神经和胸长神经
B.尺神经和胸内侧神经
C.尺神经和胸外侧神经
D.尺神经和胸背神经
E.前臂外侧皮神经
[单项选择]小儿营养性巨幼红细胞贫血多见于()
A. <2岁
B. <1岁
C. >2岁
D. >3岁
E. >4岁
[不定项选择题]共用题干
Ants Have Big Impact on Environment as“Ecosystem Engineers”
Research by the University of Exeter has revealed that ants have a big impact on their local environment as a result of their activity as“ecosystem engineers”and predators.The study,published in the Journal of Animal Ecology,found that ants have two distinct effects on their local environment.
Firstly,through moving of soil by nest building activity and by collecting food they af-fect the level of nutrients in the soil.This can indirectly impact the local populations of many animal groups,from decomposers to species much higher up the food chain.
Secondly,they prey on a wide range of other animals,including larger prey which can be attacked by vast numbers of ant workers.
Dirk Sanders,an author of the study from the university's Centre for Ecology and Con-servation,said:“Ants are very effective predators which thrive in huge numbers. They're al-so very territorial and very aggressive,defending their resources and territory against other predators. All of this means they have a strong influence on their surrounding area.”
“In this research,we studied for the first time how big this impact is and the subtleties of it.What we found is that despite being predators,their presence can also lead to an in-crease in density and diversity of other animal groups. They genuinely play a key role in the local environment,having a big influence on the grassland food web,”Sanders said.
The study,carried out in Germany,studied the impact of the presence of different com-binations and densities of black garden ants and common red ants,both species which can be found across Europe,including in the UK.It found that a low density of ants in an area in-creased the diversity and density of other animals in the local area,particularly the density of herbivores and decomposers. At higher densities ants had no or the opposite effect,showing that predation is counteracting the positive influence.
Dr Frank van Veen,another author on the study,said:“What we find is that the impact of ants on soil nutrient levels has a positive effect on animal groups at low levels,but as the number of ants increases,their predatory impacts have the bigger effect一thereby counter-acting the positive influence via ecosystem engineering.”
Ants are important components of ecosystems not only because they constitute a great part of the animal biomass but also because they act as ecosystem engineers.Ant biodiversity is incredibly high and these organisms are highly responsive to human impact,which obvi-ously reduces its richness. However,it is not clear how such disturbance damages the main-tenance of ant services to the ecosystem. Ants are important in below ground processes through the alteration of the physical and chemical environment and through their effects on plants,microorganisms,and other soil organisms.
As predators,ants______.
A.prey on small as well as large animals
B.collect nutritious food from the soil
C.collect food as decomposers
D.prey on species much higher up the food chain
[单选题]凡在坠落高度基准面()及以上的高处进行的作业,都应视作高处作业。
A.1m
B.2m
C.2.5m
D.3m
E.略
F.略
[单选题]( )是一种骨营养不良性疾病,常在成年动物软骨内骨化完成后发生。
A.佝偻病
B.骨软病
C.纤维性骨营养不良
D.生产瘫痪
[多选题]影响企业工资水平的内部因素包括()。
A.政府颁布的法律法规
B.企业规模
C.企业所处的发展阶段
D.企业所属行业性质
E.领导班子对工资问题的重视程度
[单选题]5.107.
营销项目资料归档应做到?
A.一类一档一个单位一档
B.一项一档
C.一物一档
[单选题]醉酒驾驶机动车在道路上行驶会受到什么处罚?
A.处2年以下徒刑
B.处拘役,并处罚金
C.处2年以上徒刑
D.处管制,并处罚金
[单选题] 用外螺纹锥打捞钻具时,下钻至距鱼顶0.5 m开泵循环( )。
A.5 min
B.10~20 min
C.30 min
D.30~60 min
[判断题]不在司机一侧作业且采用手信号调车时,推进调车的速度不得超过15km/h。
A.正确
B.错误
[单项选择]阅读郑板桥的《渔家》:“卖得鲜鱼百二钱,余粮炊饭放归船。拔来湿苇难烧着,晒在垂杨古岸边。”诗中的“百二钱”是货币在发挥如下作用()
A. 价值尺度
B. 贮藏手段
C. 流通手段
D. 支付手段