受精卵分裂成桑葚胚发生在受精后（  ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25963' and id < 2177667 and id<>'2177667' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25963' and id > 2177667 and id<>'2177667' order by id asc limit 5