Britni Schlachter Rasmussen University BSC2347/L: Anatomy & Physiology II Lab Prof. Elizabeth St. Louis
The embryonic phase lasts from the end of the first week through the eighth week after conception. It is recognized as the entire first trimester of development. The entire embryonic phase is over in 7 weeks. (Wakim et al., 2021).
There are three distinct phases outlining embryonic development. The cleavage process is the initial cell division of the zygote after conception. Gastrulation, neurulation, and organogenesis are the cellular arrangements an embryo undergoes. These processes begin the development of major organ systems within the body.