-1的相反数的倒数是______.
∵-1的相反数是1,1的倒数为1,
∴-1的相反数的倒数是:1,
故答案为:1.
正常二尖瓣开口面积为()
A.4~6cm2
B.2~4cm2
C.3~4cm2
D.1~2cm2
E.6~8cm2
分解代谢物阻遏(catabolite repression)