RE: LeoThread 2025-08-01 19:49
You are viewing a single comment's thread:
Part 3/8:
In more complex animals, the blastula undergoes a process called invagination, where part of the blastula folds inward to form a gastrula with a digestive cavity. The gastrula has distinct layers called germ layers: the outer ectoderm, the inner endoderm, and in many animals, a middle mesoderm. These layers differentiate into various tissues and organs during further development.
Invagination is vital to forming these layers, involving the folding of the outer cell sheet inward, creating structures known as blastopores and setting the stage for organogenesis. The precise processes and structures involved in embryonic development vary across species, reflecting biological diversity.