Embryology — Flashcards

Flashcard 351: What is the embryonic origin of chromaffin cells? _____

Answer: Neural crest

Flashcard 352: _____ is the absence of the skull and brain, resulting in an open calvarium with an absent forebrain

Answer: Anencephaly

Flashcard 353: The adrenal medulla is of _____ origin

Answer: neural crest

Flashcard 354: Congenital _____ is a failure of umbilical ring to close after physiologic herniation of the intestines

Answer: umbilical hernia

Flashcard 355: What is the embryonic origin of the lens of the eye? _____

Answer: Surface ectoderm

Flashcard 356: During closure of neural folds, the _____ cells form from neuroectoderm

Answer: neural crest

Flashcard 357: Which tracheoesophageal anomaly resembles the letter H? _____

Answer: Pure TEF ("H-type")

Flashcard 358: In which period of lung development do pneumocytes develop? _____

Answer: Canalicular period (weeks 16–25)

Flashcard 359: What is the embryonic origin of parafollicular cells (C cells) of the thyroid?

Answer: Neural crest cells

Extra: Parafollicular cells (C cells) are derived from **neural crest cells** (migrating into the ultimopharyngeal body, which is derived from the 4th pharyngeal pouch). In contrast, the **follicular cells** of the thyroid gland are derived from **endoderm** (the thyroid diverticulum from the floor of the pharynx).

Flashcard 360: The ganglion cells that fail to descend in Hirschsprung disease are derived from _____

Answer: neural crest