Embryology — Flashcards

Flashcard 361: Congenital _____ is a failure of umbilical ring to close after physiologic herniation of the intestines

Answer: umbilical hernia

Flashcard 362: What is the embryonic origin of the lens of the eye? _____

Answer: Surface ectoderm

Flashcard 363: During closure of neural folds, the _____ cells form from neuroectoderm

Answer: neural crest

Flashcard 364: Which tracheoesophageal anomaly resembles the letter H? _____

Answer: Pure TEF ("H-type")

Flashcard 365: 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 366: The protein S-100 is found in cells of _____ lineage (ex. Schwann cells, melanocytes)

Answer: neural crest

Flashcard 367: What congenital abnormality arises due to failure of fusion of the two lateral palatine shelves? _____

Answer: Cleft palate

Flashcard 368: Abnormal prenatal development of the acetabulum is caused by excessive _____

Answer: uterine packing (uterine constraint)

Flashcard 369: Which embryologic kidney becomes the permanent kidney? _____

Answer: Metanephros

Flashcard 370: What is the embryonic origin of Schwann cells? _____

Answer: Neural crest