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> 小明在“观察洋葱鳞片叶表皮细胞”的实验中，下列操作正确的是（　　） A．为了保证观察的效果，撕取的洋葱鳞片叶大而厚 B．视野中观察的细胞偏左下角，要移动到中心时，向右上角移动玻片 C．要想看到更多的细胞，换用放大倍数较低的目镜或物镜 D．视野中光线过暗时，应调节反光镜和光圈

问题：

发布时间：2024-09-07

小明在“观察洋葱鳞片叶表皮细胞”的实验中，下列操作正确的是（　　）

A．为了保证观察的效果，撕取的洋葱鳞片叶大而厚

B．视野中观察的细胞偏左下角，要移动到中心时，向右上角移动玻片

C．要想看到更多的细胞，换用放大倍数较低的目镜或物镜

D．视野中光线过暗时，应调节反光镜和光圈

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