蓝藻细胞和菠菜的细胞的主要区别在于蓝藻细胞没有( )
A:细胞膜
B:细胞质
C:细胞壁
D:核膜
我们常说“眼观六路,耳听八方”可见眼和耳对人体适应外界环境的重要性.图为眼球和耳的结构示意图,请据图分析回答:
The shop owner suddenly stopped talking with his mouth ________ like a big “O”. It was the President Xi Jinping.