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【简答题】
Oceanography has been defined as “The application of all sciences to the study of the sea”. Before the nineteenth century, scientists with an interest in the sea were few and far between. Certainly Newton considered some theoretical aspects of it in his writings, but he was reluctant to go to sea to further his work. For most of people, the sea was remote, and with the exception of early intercontinental travelers or others who earned a living from the sea, there was little reason to ask many questions about it, let alone to ask what lay beneath the surface. The first time that question “What is at the bottom of the ocean?” had to be answered with any commercial consequence was when the laying of a telegraph cable from Europe to America was proposed. The engineers had to know the depth profile of the route to estimate the length of cable that had to be manufactured. It was to Maury of US Navy that the Atlantic Telegraph Company turned, in 1853, for information on this matter. In the 1840s, Maury had been responsible for encouraging voyage during which soundings were taken to investigate the depths of the North Atlantic and Pacific Ocean. Later, some of his findings aroused much popular interest in his book The Physical Geography of the Sea . The cable was laid, but not until 1866 was the connection made permanent and reliable at the early attempts, the cable failed and when it was taken out for repairs it was found to be covered in living growths, a fact which defied contemporary scientific opinion that there was no life in the deeper parts of the sea. Within a few years oceanography was under way. In 1872 Thomson led a scientific expedition, which lasted for four years and brought home thousands of samples from the sea. Their classification and analysis occupied scientists for years and led to a five-volume report, the last volume being published in 1895.
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参考答案:
举一反三
【多选题】下面关于映射的说法正确的是()。
A.
映射是一种在SDH网络边界处,将支路信号适配进虚容器的过程
B.
映射的逆过程称为去映射或解映射
C.
映射有异步、比特同步、字节同步三种映射方法
D.
映射有浮动VC和锁定TU两种映射模式
【简答题】下图表示植物叶片表皮上的两个气孔,据图回答: (1)图中[     ]表示气孔,它是由一对半月形的____________细胞组成。 (2)气孔分布在叶片的__________和__________部位。 (3)植物在正常的生理活动的情况下,如果叶表皮上的气孔处于图甲所示的状态,此时: a.白天进行光合作用:___________通过气孔进入,____________通过气孔出来; b.晚上进行呼...
【单选题】患者男性,间断上腹痛6年,加重2周,呕血、黑便6小时,被诊断为胃溃疡大出血,全麻下行“毕I式胃大部分切除术”术后患者出现顽固性呃逆,首先应考虑的原因是
A.
手术造成神经中枢受刺激
B.
术后血肿刺激腹腔神经丛
C.
术后肠粘连导致肠梗阻
D.
膈下感染
【判断题】映射是一种在SDH网络边界处,将支路信号适配进容器的过程。
A.
正确
B.
错误
【多选题】气孔由两个 [填空(1)] 细胞组成,气孔的运动表现为气孔的 [填空(2)] 和 [填空(3)] 。
A.
保卫
B.
C.
【简答题】如图表示植物叶片表皮上的两个气孔,据图回答: (1)图中[______]表示气孔,它是由一对半月形的______细胞组成.[______]表示叶绿体. (2)植物在正常的生理活动的情况下,如果叶表皮上的气孔处于图甲所示的状态,此时: a光合作用:______通过气孔进入,______通过气孔出来; b呼吸作用:______通过气孔进入,______通过气孔出来; c蒸腾作用:______以气体状态...
【判断题】( )映射是一种在SDH网络边界处,将支路信号适配进容器的过程。
A.
正确
B.
错误
【单选题】伟大的物理学家法拉第是电磁学的奠基人,在化学、电化学、电磁学等领域都做出过杰出贡献,下列陈述中不符合历史事实的是
A.
法拉第首先引入 “场”的概念来研究电和磁的现象
B.
法拉第首先引入电场线和磁感线来描述电场和磁场
C.
法拉第首先发现了电流的磁效应现象
D.
法拉第首先发现电磁感应现象并给出了电磁感应定律
【单选题】上腹痛部手术后出现顽固性呃逆,首先考虑的原因是
A.
膈下感染
B.
胃潴留
C.
腹膜后血肿
D.
肠粘连
E.
手术造成隔神经损伤
【简答题】双子叶植物气孔由______形的保卫细胞组成,而单子叶植物的气孔则由两个______形的保卫细胞和两个______细胞组成。
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