Embryology Flashcards
During the 4th embryonic development, the tongue appears in the form of two lingual swellings and one medial swelling, the so-called:
Tuberculum impar
Cartilages of 1st and 2nd arches are derived from
Neural crest cells
Cartilages of the fourth-sixth brachial arches are derived from
Mesoderm
Developmental defect affects the derivatives of the first branchial arch. Exhibits micrognathia, malar, hypoplasia, deformity of the lower rim of the orbit and malformed external ear.
Mandibulofacial dysostosis
Failure of fusion of which of the following will lead to cleft lip?
Maxillary process; medial nasal process
The first portion of the face to form after a he creation of the stomodeum
Mandible
Failure of fusion of palatine shelves will lead to
Cleft palate
During the fourth week the of embryonic development, the first branchial arch divides to form:
Mandibular and maxillary processes or also called as max and man prominences
It is a faint ridge in the midline that on the surface of the bony mandible where the mandible is formed by the fusion of the mandibular processes
Mandibular symphysis
The second branchial arch gives rise to the:
Palatine tonsil
1st pharyngeal pouch gives rise to:
Formation of tympanic membrane, auditory tubes tympanic cavity, mastoid antrum
3rd pharyngeal pouch gives rise to:
Inferior parathyroid glands (from the dorsal part) and
Thymus gland (ventral)
3rd pharyngeal arch gives rise to:
Superior parathyroid glands (dorsal)
5th pharyngeal pouch gives rise to:
Ultimobranchial bodies ( gives rise to C cells of the thyroid)
C cells of the thyroid is responsible to secreting:
Calcitonin
1st branchial CLEFT forms the
External auditory meatus
Congenital malformation caused by underdevelopment of 4th and 5th branchial pouches leading to absence or hypoplasia or the parathyroid glands. The patients usually have congenital heart defects and compromised immunity
Digeorge syndrome
The thyroid gland is first identifiable during the fourth week of gestation, beginning as an endodermal invagination of the tongue at the site of:
Foramen cecum
The primary palate or median palatal process is formed by the merging of the frontonasal process with which other processes?
Medial nasal process
Completion of the palate is during:
12th week of prenatal development
The nasal cavities are formed from what embryonic structure?
Nasal pits
The following are neural crest cells derivatives:
Melanocytes
Dorsal root ganglia
Adrenal medulla
Autonomic ganglia
Schwann cells
Sensory ganglia of cranial nerves
