下列关于哺乳动物胚胎发育和胚胎工程的叙述,正确的是 A.卵裂

 下列关于哺乳动物胚胎发育和胚胎工程的叙述,正确的是

A.卵裂期胚胎中细胞数目和有机物总量在不断增加

B.胚胎分割时需将原肠胚的内细胞团均等分割

C.胚胎干细胞具有细胞核大、核仁小和蛋白质合成旺盛等特点

D.胚胎干细胞是一类未分化细胞,可从早期胚胎中分离获取

答案

 D

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