常用于偏酸性抗原标记的生物素是()
A.BNHS
B.BCNHS
C.BCHZ
D.MPB
E.BHZ
参考答案:E
Atisas of World History 一书中写道:“The old feudal (封建的) system of government was abolished and a system of prefects (官员) was introduced by Qin Shi Huangdi (秦始皇). ” 这里的“feudal system”指的是( )
A.三公九卿制
B.分封制
C.郡县制
D.三省六部制
植物繁殖方式?