abnormal triploblastic development abnormal endoderm development GO:0001706 MP:0001685 MP:0001686 MPheno.ontology abnormal definitive endoderm development abnormal endoderm differentiation abnormal entoderm development any abnormality in the formation of the innermost of the three primary germ layers of the embryo (the others being mesoderm and ectoderm) during gastrulation; endoderm gives rise to the epithelial lining of the gastrointestinal and respiratory tracts; the parenchyma of the tonsils, the liver, the thymus, the thyroid, the parathyroids, and the pancreas; the epithelial lining of the urinary bladder, urethra, and prostate; and the epithelial lining of the tympanic cavity, tympanic antrum, and auditory tube