下图是根据细胞器的相似或不同点进行分类的,下列哪一选项不能作为此图分类依据
A.有无膜结构
B.单层膜还是双层膜
C.是否含有色素
D.是否普遍存在于动植物细胞中
答案:A
Could it be in the place ______ we visited yesterday ______ you left your book?
A.that; which
B.in which; where
C.where; that
D.that; that
薄层色谱法的固定相有
A.硅胶H
B.硅胶G
C.氧化铝
D.滤纸
E.聚酰胺