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【简答题】
最早提出的DNA二级结构并非双螺旋,而是由Linus Pauling 和Robert Corey 于1952 年提出的三螺旋结构。三螺旋结构认为,DNA由三条链组成,不同的碱基在分子的外部,而磷酸在内部,分子是螺旋的。给出至少五条理由,为什么这样的三螺旋结构是不正确的(每点4分)。这两位科学家又是基于什么原因提出三螺旋模型,给出至少两条理由(每点5分)。
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【单选题】Before the findings released by the Kaiser Family Foundation,activists worried that
A.
the Americans might not concern about AIDS any more
B.
the government is too optimistic about the cure of AIDS
C.
the deaths caused by AIDS may increase.
D.
scientists may not find cures for AIDS.
查看完整题目与答案
【单选题】Attitudes to AIDS Now Most people say that the USA is making progress in fighting AIDS, but they don't know there's no cure and strongly disagree that 'the AIDS epidemic is over,' a new survey finds. ...
A.
Recent news about AIDS is not tree.
B.
People may stop worrying about AIDS.
C.
Deaths caused by AIDS may not decline.
D.
Advances in AIDS treatment are too slow.
查看完整题目与答案
【单选题】AIDS activists permanently changed and shortened America’s ______ process for testing and approving new drugs of all kinds, for all diseases.
A.
efficient
B.
stagnant
C.
intricate
D.
appropriate
查看完整题目与答案
【判断题】第二次世界大战结束时,形成了以量子论,相对论和核物理学三大分支为主流的现代物理学体系。
A.
正确
B.
错误
查看完整题目与答案
【简答题】Please match the terms according to the definitions. Answer with the corresponding letters (a,b,c...)(请填写相应的字母序号。) Terms: a.bound morpheme b . base c . morpheme d. free morpheme e. affix f . deriv...
查看完整题目与答案
【单选题】_______ is a minimal meaningful linguistic unit of language, not divisible or analyzable into smaller forms.
A.
word
B.
phoneme
C.
morpheme
D.
syllable
查看完整题目与答案
【单选题】Before the findings released by the Kaiser Family Foudation, activists worried that
A.
the government is too optimistic about the cure of AIDS
B.
the Americans might not concern about AIDS any more
C.
the deaths caused by AIDS may increase
D.
scientists may not find cures for AIDS
查看完整题目与答案
【单选题】老王和他的老伴与太原某旅行社签订了云南五日游合同,在旅游行程中,因组团社与地接社工作衔接不当,导致部分景点未能游览,总计有一天的游程没有被实际履行; 回来后,老王夫妇要求旅行社安排补玩“缩水妙的行程。关于本案,下列说法正确的是
A.
安排补玩合理，旅行社应承担继续履行的违约责任
B.
安排补玩不合理，旅行社应承担赔偿损失的责任
C.
安排补玩合理，旅行社还应双倍赔偿游客
D.
安排补玩不合理，旅行社应全额返还游客旅游费用
查看完整题目与答案
【单选题】The new breed of environmental activists differed from the previous activists in that______.
A.
they noticed environmental disparities between the rich and the poor
B.
they cried for government intervention in saving the environment
C.
they knew what 'the environment' really meant to the White people
D.
they practiced environmentalism outside as well as within the US
查看完整题目与答案
【单选题】Attitudes to AIDS Now Most people say that the USA is making progress in fighting AIDS, but they don't know there's no cure and strongly disagree that 'the AIDS epidemic is over,' a new survey finds. ...
A.
Recent news about AIDS is not true.
B.
People may stop worrying about AIDS.
C.
Deaths caused by AIDS may not decline.
D.
Advances in AIDS treatment are too slow.
查看完整题目与答案
相关题目：
【单选题】Before the findings released by the Kaiser Family Foundation,activists worried that
A.
the Americans might not concern about AIDS any more
B.
the government is too optimistic about the cure of AIDS
C.
the deaths caused by AIDS may increase.
D.
scientists may not find cures for AIDS.
查看完整题目与答案
【单选题】Attitudes to AIDS Now Most people say that the USA is making progress in fighting AIDS, but they don't know there's no cure and strongly disagree that 'the AIDS epidemic is over,' a new survey finds. ...
A.
Recent news about AIDS is not tree.
B.
People may stop worrying about AIDS.
C.
Deaths caused by AIDS may not decline.
D.
Advances in AIDS treatment are too slow.
查看完整题目与答案
【单选题】AIDS activists permanently changed and shortened America’s ______ process for testing and approving new drugs of all kinds, for all diseases.
A.
efficient
B.
stagnant
C.
intricate
D.
appropriate
查看完整题目与答案
【判断题】第二次世界大战结束时,形成了以量子论,相对论和核物理学三大分支为主流的现代物理学体系。
A.
正确
B.
错误
查看完整题目与答案
【简答题】Please match the terms according to the definitions. Answer with the corresponding letters (a,b,c...)(请填写相应的字母序号。) Terms: a.bound morpheme b . base c . morpheme d. free morpheme e. affix f . deriv...
查看完整题目与答案
【单选题】_______ is a minimal meaningful linguistic unit of language, not divisible or analyzable into smaller forms.
A.
word
B.
phoneme
C.
morpheme
D.
syllable
查看完整题目与答案
【单选题】Before the findings released by the Kaiser Family Foudation, activists worried that
A.
the government is too optimistic about the cure of AIDS
B.
the Americans might not concern about AIDS any more
C.
the deaths caused by AIDS may increase
D.
scientists may not find cures for AIDS
查看完整题目与答案
【单选题】老王和他的老伴与太原某旅行社签订了云南五日游合同,在旅游行程中,因组团社与地接社工作衔接不当,导致部分景点未能游览,总计有一天的游程没有被实际履行; 回来后,老王夫妇要求旅行社安排补玩“缩水妙的行程。关于本案,下列说法正确的是
A.
安排补玩合理，旅行社应承担继续履行的违约责任
B.
安排补玩不合理，旅行社应承担赔偿损失的责任
C.
安排补玩合理，旅行社还应双倍赔偿游客
D.
安排补玩不合理，旅行社应全额返还游客旅游费用
查看完整题目与答案
【单选题】The new breed of environmental activists differed from the previous activists in that______.
A.
they noticed environmental disparities between the rich and the poor
B.
they cried for government intervention in saving the environment
C.
they knew what 'the environment' really meant to the White people
D.
they practiced environmentalism outside as well as within the US
查看完整题目与答案
【单选题】Attitudes to AIDS Now Most people say that the USA is making progress in fighting AIDS, but they don't know there's no cure and strongly disagree that 'the AIDS epidemic is over,' a new survey finds. ...
A.
Recent news about AIDS is not true.
B.
People may stop worrying about AIDS.
C.
Deaths caused by AIDS may not decline.
D.
Advances in AIDS treatment are too slow.
查看完整题目与答案