What is embryological origin of digestive …

The gastrointestinal tract (GIT) arises initially during the process of gastrulation from the endoderm of the trilaminar embryo (week 3) and extends from the buccopharyngeal membrane to the cloacal membrane. The tract and associated organs later have contributions from all the germ cell layers.

While crown formation is accomplished during embryonic development, tooth root formation occurs in mice molar teeth at postnatal stages and lasts for up to three weeks. During root formation, cemento blasts are formed from the mesenchymal tooth compartment and secrete cementum, which surrounds the forming tooth root.

As part of embryonic development, the pancreas forms as two buds from the fore gut, an embryonic tube that is a precursor to the gastrointestinal tract. It is therefore of endodermal origin. Pancreatic development begins with the formation of a dorsal and ventral pancreatic bud.