问题 判断题

地球上最早的生命起源于原始的海洋。(    )

答案

考点:

分析:此题考查的知识点是生命的起源.解答时可以从原始生命的起源过程方面来切入.

解答:解:原始大气中没有氧气,因此原始地球上没有生命.后来在高温、雷电、紫外线的作用下,在原始大气中产生了简单的有机物;有机物随着雨水一起汇入原始海洋.原始海洋就像一盆稀薄的热汤,其中所含有的有机物,不断的相互作用,经过漫长的岁月,大约在地球形成以后的10亿年左右,才形成了具有生命现象的复杂的有机物.即原始生命.因此原始海洋是原始生命的摇篮.

故答案为:√.

点评:解答此类题目的关键是熟记原始生命起源于原始海洋.

选择题
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When I was at university, I studied very hard. But a lot of my friends did very little work. Some did just enough to pass exams. Others didn't do quite enough. Fred Baines was one of them. He spent more time drinking in the Students' Union than working in the library.

Once, at the end of the term, we had to take an important test in chemistry. The test had a hundred questions. Beside each question, we had to write "True" or "False". While I was studying in my room the night before the test, Fred was watching television. Fred usually worried a lot the night before a test. But on that night he looked perfectly calm. Then he told me of his plan.

"It's very simple. There are a hundred questions and I have to get fifty correct to pass the test. I'll take a coin into the examination room. I haven't studied a chemistry book for months, so I'll just toss(抛) the coin. That way, I'm sure I'll get half the questions right."

The next day Fred came cheerfully into the examination room. He sat tossing a coin for half an hour as he marked down his answers. Then he left, half an hour before the rest of us.

The next day, he saw the chemistry professor in the corridor (走廊).

"Oh, good," he said. "Have you got the result of the test? What mark did I get?"

The professor looked at him and smiled.

"Ah, it's you, Baines. Just a minute."

Then he reached into his pocket and took out a coin. He threw it into the air, caught it in his hand and looked at it.

"I'm terribly sorry, Baines," he said, "you failed."

61. Fred Baines          .

A. spent quite some time working in the Students' Union

B. worked hard at his lessons but he failed again and again

C. often failed his tests

D. wouldn't work hard so long as he could pass a test

62. Fred looked perfectly calm before the chemistry test because        .

A. he was already well prepared for it

B. he didn't think the test was so important for him

C. someone had promised to help him out

D. he believed he had found out a way to pass the test without any difficulty

63. The students were required to finish the test within       .

A. half an hour   B. an hour   C. three quarters   D. an hour and a half

64. After the test, Baines was       .

A. sure that he would pass it            

B. anxious to know the result

C. sorry that he cheated during the test  

D. discouraged because he'd probably fail the test

65. The professor told Baines the result of the test by tossing a coin because     .

A. he hadn't marked all the papers yet  

B. he couldn't remember the mark Baines got

C. he wouldn't hurt Baines' feeling by telling him the truth

D. he wanted to teach Baines a lesson