题目

右图表示的果蝇可形成基因型为ABRc的卵细胞,则该果蝇减数分裂时发生互换最多能形成的卵细胞种类数分别是 A.16 B.8 C.4 D.2 答案：AWith more and more forests _____, some animals and plants are facing the danger of dying out. [     ]A. damagedB. damaging C. having damagedD. have been damaged