Embryonic coelom

Embryonic coelom is a significant structure that forms during the embryogenesis of higher organisms, including vertebrates. It is a fluid-filled cavity that separates the mesoderm into two layers, the parietal (or somatic) and the visceral (or splanchnic) mesoderm. The embryonic coelom plays a crucial role in the development of the body cavities and the positioning of internal organs.

Formation

The embryonic coelom forms during the third week of human embryonic development. It begins as isolated coelomic spaces within the lateral plate mesoderm. These spaces gradually merge to form the intraembryonic coelom, a single horseshoe-shaped cavity. The coelom is initially open to the extraembryonic coelom but becomes separated when the primitive gut forms.

Function

The embryonic coelom serves as the primordium for the ventral body cavity, which eventually divides into the thoracic cavity, abdominal cavity, and pelvic cavity. The coelom also contributes to the formation of the pleura, pericardium, and peritoneum, the membranes that line these cavities and envelop the internal organs.

Clinical Significance

Abnormalities in the formation of the embryonic coelom can lead to a variety of congenital defects, such as diaphragmatic hernia, congenital heart defects, and gastroschisis. Understanding the development and function of the embryonic coelom is therefore crucial in prenatal diagnosis and treatment.

See Also

• Embryogenesis
• Mesoderm
• Human embryonic development

References

• Gilbert, S.F. (2000). Developmental Biology. Sunderland, MA: Sinauer Associates.
• Moore, K.L., Persaud, T.V.N., & Torchia, M.G. (2015). The Developing Human: Clinically Oriented Embryology. Philadelphia, PA: Elsevier.