题干

高等哺乳动物受精后不久,受精卵开始进行细胞分裂。经桑椹胚、囊胚、原肠胚和组织器官的分化,最后发育成一个完整的幼体,完成胚胎发育的全过程,下列有关叙述错误的是

A:题图是胚胎发育过程中囊胚期示意图,①②③依次称之为透明带、滋养层、内细胞团

B:高等哺乳动物胚胎发育经历的时期是受精卵→卵裂期→桑椹胚→囊胚期→原肠胚期→幼体,其中,最关键的时期是原肠胚期

C:高等哺乳动物胚胎发育中的细胞分化开始于囊胚期,终止于生命结束

D:进行胚胎分割时,应选择原肠胚期的胚胎进行

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D

同类题4

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