Part 3/9:
Morphogenetic Movements: Gastrulation
The transition from the blastula to a more structured embryo marks the beginning of gastrulation. This critical stage involves morphogenetic movements—cell movements that transform the simple blastula into a structure with distinct layers known as germ layers. These three germ layers—the ectoderm, mesoderm, and endoderm—are the foundational tissues from which all future organs and tissues develop.
Gastrulation effectively reorganizes the embryo's cell mass, establishing the future body plan and internal organization. The signals exchanged during this process are crucial for the correct positioning of tissues and for subsequent organ development.