Tags: Anatomical Structure, Embryology.
An embryo is a multicellular diploid eukaryote in its earliest stage of development from the time of first cell division until birth hatching or germination. In humans it is called an embryo until about eight weeks after fertilization (i.e. ten weeks after the last menstrual period or LMP) and from then it is instead called a fetus.The development of the embryo is called embryogenesis.