| Every living thing has an inner
biological clock that controls behavior. The clock works all the time; even when
there are no outside signs to mark the passing of time. The biological clock
tells plants when to form flowers and when the flowers should open. It tells
insects when to leave the protective cocoon and fly away. And it tells animals
when to eat, sleep and wake. It controls body temperature, the release of some
hormones and even dreams. These natural daily events are circadian
rhythms. Man has known about them for thousands of years. But the first scientific observation of circadian rhythms was not made until 1729. In that year a French astronomer, Jean Jacques d’Ortous de Mairan, noted that one of his plants opened its leaves at the same time every morning, and closed them at the same time every night. The plant did th A. even when it was put in a murky place all day. B. even if it was placed in the moonlight. C. even when he was observing it from a dark place. D. even if it was kept in a dark place from time to time. [判断题]从境外汇入的捐赠外汇资金
A.正确 B.错误 [多选题]探放水起点确定依据有（ ）。
A.积水线 B.探水线 C.警戒线 D.水位线 [单项选择]在世界发现的古人类中被公认为首先使用天然火的是（）
A. 北京猿人 B. 河姆渡人 C. 半坡人 D. 元谋人 [判断题]1551弹簧操作机构是利用弹簧瞬间释放的能量完成断路器的合闸的。( )
A.正确 B.错误 [多选题]利用消防梯登高开辟外攻路线时有（）等风险时，不得将身体固定在消防梯上，做好紧急避险。
A.倒塌 B.轰燃 C.高温 D.浓烟 [简答题]《铁路旅客运输服务质量规范》（铁总运〔2016〕247号）规定，客运人员素质有何要求?
[判断题] 用碳钢制作的水箱,内壁应有良好的防腐层。
A.正确 B.错误 [单项选择]手机动漫3元包每月可以免费发送多少条彩漫？（）
A. 30 B. 40 C. 50 D. 60 [判断题]配送中心一旦接受到客户退货信息要求，就必须坚持原则，一般不予退货。
A.正确 B.错误 [多项选择]泳池非开放期间，泳池管理员至少每（）一次、主管人员至少每（）一次、部门负责人至少每（）一次对泳池现场进行巡查。依次顺序为（）。
A. 天 B. 周 C. 月 D. 季 E. 年 我来回答: 提交
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