Determination

The developmental process in which cells and tissues of the embryo become progressively restricted in what they may become.  Cells of the early embryo may be totipotent, capable of producing cells of any organ system of the adult.  As development proceeds, however, cells become increasingly limited in their potential and directed toward a definite structure and function (cf. stem cells).  

See Canalization, Developmental plasticity, Differentiation (embryology), Equipotentiality, Induction (embryology), Stem cells