用吸管从草履虫培养液中吸取草履虫的最好部位是A.培养液的下层 

用吸管从草履虫培养液中吸取草履虫的最好部位是

A.培养液的下层                                                      B.培养液的表层

C.培养液的中层                                                      D.培养液的任一部位

 

答案

B

解析:略

 

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