Embryology — Flashcards

Flashcard 361: Breast tissue can develop anywhere along the _____, which runs from the axilla to the vulva (e.g. supernumerary nipples)

Answer: milk line

Flashcard 362: The neural tube begins as _____ (number) primary vesicles

Answer: three

Flashcard 363: The most superior of the 3 primary vesicles (developing brain) is the _____

Answer: forebrain (prosencephalon)

Flashcard 364: Which branchial arch gives rise to all intrinsic muscles of the larynx, except the cricothyroid? _____

Answer: 6th arch

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: What is the embryonic origin of Schwann cells? _____

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: What is the embryonic origin of the peritoneum (serous lining of cavities)? _____

Answer: Mesoderm

Flashcard 370: What is the most common site of obstruction (hydronephrosis) in the fetal kidney? _____

Answer: Ureteropelvic junction