I.下图为人类中的一种单基因遗传病系谱图。请回答: 仅根据该系谱图,不能确定致病基因是位于常染色体上,还是位于X染色体上。如果致病基因位
Doris Lessing was born in 1919 in Persia, moving as a child with her family to southern Rhodesia, now Zimbabwe, where she stayed in school only to the age of 14. A year after moving to London, she pub
下列化学方程式书写正确的是 ( ) A.甲烷的标准燃烧热为-890.3kJ·mol-1,则甲烷燃烧的热化学
Surfing—the art of riding a wave on a pointed board—is the wildest, fastest natural water sport known to man. In recent years, it has developed into a major sport around the world, from Australia
我市是全国十大宜居城市之一,人们对空气污染关注的程度不断加强,下列气体中不会造成空气污染的是A. 二氧化氮 B.二氧化硫
命题“若a、b都是偶数,则a+b是偶数”的逆否命题是___________.
(07广东卷)高等植物的两种重要生理过程I和II通过a、b、c、d四种物质紧密联系在一起(见右图),其中a和d最可能是 ① CO2 ② O
氧化还原反应发生在同种元素之间的是 ( ) A.Zn+2HCl=ZnCl2+H2