Embryogenesis is the process by which a fertilized egg develops into a fully formed embryo. It begins with the union of a sperm and an egg, forming a zygote. This zygote undergoes multiple cell divisions, leading to the formation of a blastocyst, which eventually implants into the uterus in mammals. During embryogenesis, cells differentiate into various types, forming the basic structures of the organism. This includes the development of tissues, organs, and body systems. The process is guided by genetic instructions and involves complex signaling pathways that ensure proper growth and development.