somite embryo

embryo /em·bryo/ (em´bre-o)

1. in animals, those derivatives of the zygote that eventually become the offspring, during their period of most rapid growth, i.e., from the time the long axis appears until all major structures are represented.

2. in humans, the developing organism from fertilization to the end of the eighth week. Cf. fetus.

3. in plants, the element of the seed that develops into a new individual.em´bryonalembryon´ic

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presomite embryo  the embryo at any stage before the appearance of the first somite.

previllous embryo  the embryo before the placental chorionic villi develop.

somite embryo  the embryo between the appearance of the first and the last somites.

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somite embryo,

an embryo in any stage of development between the formation of the first and the last pairs of somites, which in humans occurs in the third and fourth weeks after fertilization of the ovum.