Embryonic Development

All the events which change a zygote into a fully developed organism is called embryonic development. The entire process of development is called embryogenesis. Von Bear is called the "Father of Modern Embryology".

Embryonic Development includes a definite series of fundamentally similar sequence of events. It includes

• Gametogenesis - Formation of gametes

• Fertilisation - Fusion of male and female gamete to form zygote.

• Cleavage - Division of zygote by mitosis to form a hollow blastula.

• Gastrulation - Movement and rearrangement of embryonic cells to form three primary germinal layers.

• Organogenesis - The formation of specific organ systems from the three germinal layers.