器官发育的基本过程 Development: series oforderly, precise steps that transform a zygote into a multicellular embryo early stage of development of multicellular organism Fertilization Preimplantation Gastrulation Organogenesis and and growth Patterning Development of the embryo: from one cell to many器官发育的基本过程 Development: series of orderly, precise steps that transform a zygote into a multicellular embryo ~early stage of development of multicellular organism Fertilization Preimplantation Gastrulation and Patterning Organogenesis and Growth Development of the embryo: from one cell to many