-Cell potency: Potential to differentiate into different cell types.
-Development: A process where something grows or changes and becomes more advanced. -Differentiation: Qualitative change in structure for an assigned function.
-Embryo: Developing individual during the first two months or eight weeks of intrauterine life (IUL). Embryo (G): (en = with in; bruein = to swell or to be full); Logos = study. -Embryology: Study of development of an individual before birth.
-Fertilization: Process of fusion of male and female gametes. It takes place in the uterine tube of female genital tract.
-Fetus: Developing individual from 3rd month or 9th week of intrauterine life to time of birth.
-Gametogenesis: This is the process of production of gametes in gonads or sex organs. In males it is known as spermatogenesis and in females as oogenesis.