细菌的形状取决于（）。
A.它们染色体中含有的遗传物质
B.它们细胞壁的构成成分
C.是否形成穿孢
D.它们细胞质中的细胞骨架位置
参考答案：A
---Which of the following sentences is CORRECT?
A．I don’t know when will he come back tomorrow.
B．I have no idea when will he come back tomorrow.
C．I don’t know when he will come back tomorrow.
D．I have no idea when is he coming back tomorrow.
镜面反射（）
A.当界面大于波长时发生
B.当界面小于波长时发生
C.由于界面小于3mm而发生
D.与入射角无关
E.以上都不是
