某一合子有两对同源染色体A和a及B和b。你预期在它们生长期时,体细胞的染色体组成是()。
A、AaBB
B、AABb
C、AaBb
D、AABB
参考答案:C
点A(-2,-3)关于原点的对称点为A′,则A′点的坐标为______.
Dick, it's the _______ time in three days that you _______ the same mistake.
A.second; have made
B.second, make
C.two; have made
D.two, will make