p Flashcards
When does the primitive gut begin to form?
The primitive gut begins to form in the fourth week of development.
What does the endoderm contribute to the gastrointestinal (GI) tract?
The endoderm gives rise to most of the epithelium and glands of the GI tract, except for the cranial and caudal extremities.
Which germ layer contributes to the epithelium of the cranial and caudal extremities of the GI tract?
The ectoderm contributes to the epithelium of the cranial and caudal extremities of the GI tract.
What tissues does the mesoderm contribute to the digestive tract?
The mesoderm contributes the muscular tissue and connective tissue of the digestive tract wall.
Into what three regions is the primitive gut divided?
The primitive gut is divided into the foregut, midgut, and hindgut.
What triggers gut tube formation?
Gut tube formation is triggered by retinoic acid (RA) from the pharynx.
Which gene does retinoic acid (RA) activate to specify the esophagus and stomach?
RA activates the SOX2 gene to specify the esophagus and stomach.
Which gene is responsible for specifying the duodenum?
The PDX1 gene specifies the duodenum.
What gene is responsible for specifying the small intestine?
The CDXC gene specifies the small intestine.
Which gene specifies the large intestine and rectum?
The CDXA gene specifies the large intestine and rectum.
