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[简答题] Chimpanzees
1 Chimpanzees (黑猩猩) will soon be extinct (灭绝). If the present rate of hunting and habitat (栖息地) destruction continues, then within 20 years, there will be no chimpanzees living in the wild. But this is more than an environmental or moral tragedy (悲剧). Chimpanzee extinction may also have profound implications (含意) for the survival of their distant relatives - human beings.
2 In 1975 the biologist Marie-Claire King and Allan Wilson discovered that the human and chimpanzee genomes (基因组) match by over 98%. Compare this to the mouse,used as model for human disease in lab tests, which shares only 60% of its DNA with us. In fact, chimpanzees are far more similar to humans than they are to any other species of monkey. As well as resembling us genetically, chimps are highly intelligent and able to use tools. These facts alone should be enough to make protection of chimps an urgent priority (优先). But there is another, more s
[简答题]CH2=CH2→CH2CH2CH2CH2OH
[简答题]CH2=CH-CH3→CH2BrCH2Cl
[单项选择]有一系列有机物按以下顺序排列:CH3CH=CHCHO,CH3(CH=CH)2CHO,CH3(CH=CH)3CHO,……,在该系列有机物中,分子中含碳元素的质量分数的最大值接近于( )。
A. 95.6%
B. 92.3%
C. 85.7%
D. 75.0%
[填空题]蛋氨酸CH3SCH2CH2CH(NH2)COOH ( )
[填空题]
要制备高产率的CH3CH2NH2,反应物CH3CH2CH2Br和NH3中过量的应该是()
[单项选择]昆虫能分泌信息素。下列是一种信息素的结构简式:
CH3(CH2)5CH=CH(CH2)9CHO
下列说法正确的是:
A. 这种信息素不可以与溴发生加成反应
B. 它可以发生银镜反应
C. 它只能与1molH2发生加成反应
D. 它是乙烯的同系物
[简答题]亲核性大小:a.C6H5O-;b.CH3CH2CH2CH2O-;c.(CH3)3CO-
[单项选择]
昆虫能分泌信息素。下列是一种信息素的结构简式:
CH3(CH2)5CH=CH(CH2)9CHO
下列说法正确的是()。
A. 这种信息素不可以与溴发生加成反应
B. 它可以发生银镜反应
C. 它只能与1molH
2发生加成反应
D. 它是乙烯的同系物
[单项选择]
昆虫能分泌信息素。
下列是一种信息素的结构简式:
CH3(CH2)5CH=CH(CH2)9CHO
下列说法正确的是()。
A. 这种信息素不可以与溴发生加成反应
B. 它可以发生银镜反应
C. 它只能与1molH
2发生加成反应
D. 它是乙烯的同系物