The anatomical parts that make up a mammalian organism in the early stages of development.

The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.

Synonyms: Embryo, Mammalian, Structures, Mammalian Embryonic, Embryos, Mammalian, Structures, Mammalian Embryo, Mammalian Embryonic Structures, Mammalian Embryo Structures, Structure, Mammalian Embryo, Mammalian Embryonic Structure, Mammalian Embryo Structure, Embryo Structures, Mammalian, Embryonic Structures, Mammalian, Mammalian Embryos, Embryonic Structure, Mammalian, Embryo Structure, Mammalian, Structure, Mammalian Embryonic, Mammalian Embryo