Science glossary film: Embryo

An animal fetus in the earliest stages of development; in humans, in the first eight weeks after fertilization. From the very first cell division, the fetus will grow to around 2.5 centimeters after eight weeks, and by the end of this developmental stage will have begun to form eyes and other internal organs, and become capable of some movement.

From the very first cell division, the fetus will grow to around 2.5 centimeters after eight weeks, and by the end of this developmental stage will have begun to form eyes and other internal organs, and become capable of some movement.