Mammals do not have a rigid cell differentiation pattern and cell count like the organism C elegans. Embryonic differentiation is the process of development during which embryonic cells specialize and diverse tissue structures arise.The differentiation of cells during embryogenesis is the key to cell, tissue, organ and organism identity. Once an egg is fertilized by a sperm, a zygote is formed. The zygote divides into multiple cells in a process known as cleavage, triggering the beginning of embryonic differentiation.
