Flashcards in Embryology of the Head & Neck Deck (85)
Stomodeum gives rise to the ____.
Frontal nasal prominence gives rise to the ____.
How many pairs of pharyngeal arches form?
1st pharyngeal arch has 2 sub units: ____ and ____.
maxillary and mandibular prominences
Formation of pharyngeal arches is driven by proliferation and migration of ____.
neural crest cells
Pharyngeal arches are covered by ____. lined by ____, with a core made up of ____.
ectoderm, endoderm, mesenchyme
1st pharyngeal arch is innervated by ____.
CN V - Trigeminal
2nd pharyngeal arch is innervated by ____.
CN VII - Facial
3rd pharyngeal arch is innervated by ____.
CN IX - Glossopharyngeal
4th & 6th pharyngeal arches are innervated by ____.
CN X - Vagus
The 1st pharyngeal arch differs from the others, in that it is lined predominantly by ____.
Pharyngeal ____ separate the arches from the outside.
Pharyngeal ____ separate the arches from the inside.
The ____ is where the ectoderm and endoderm come together at the grooves/pouches.
neural crest derivatives of arch 1 - maxillary prominence
facial bones (maxillary, zygomatic, squamous portion of temporal)
neural crest derivatives of arch 1 - mandibular prominence
Meckel's Cartilage - mandible, inner ear bones (incus & malleus), anterior ligament of malleus
neural crest derivatives of arch 2
Reichart Cartilage - lesser cornu of hyoid (superior), stylohyoid ligament, styloid process, stapes
neural crest derivatives of arch 3
body & greater cornu of hyoid (inferior)
neural crest derivatives of arch 4/6
thyroid & cricoid cartilage
mesoderm derivatives of arch 1
muscles of mastication (temporalis, masseter, mylohyoid, ant. digastric, tensor tympani)
mesoderm derivatives of arch 2
muscles of facial expression (buccinator, orbicularis oris, frontalis, etc), stylohyoid, & post. digastric
mesoderm derivatives of arch 3
mesoderm derivatives of arch 4/6
pharyngeal constrictors, m. of soft palate, & m. of larynx
sensory innervation of arch 1
CN V - somatosensation of face, teeth, palate, and ant. 2/3 of tongue
sensory innervation of arch 2
CN VII - taste to ant. 2/3 of tongue
sensory innervation of arch 3
CN IX - taste and somatosensory to post. 1/3 of tongue
sensory innervation of arch 4/6
CN X - taste and somatosensory to pharynx, larynx & esophagus
endoderm derivative of pharyngeal pouch 1
middle ear cavity & auditory tube
endoderm derivative of pharyngeal pouch 2
endoderm derivative of pharyngeal pouch 3
inferior parathyroid glands & thymus
endoderm derivative of pharyngeal pouch 4/6
superior parathyroid glands & ultimopharyngeal bodies
derivative of pharyngeal groove 1
external auditory meatus
derivative of pharyngeal grooves 2-4
cervical vesicle, which eventually degrades
Cervical cyst/fistula/sinus occurs due to incomplete degradation of the ____.
The ____ forms as a diverticulum in the endoderm between pharyngeal arch 1 & 2.
The ____ connects the thyroid primordium with the ____ and eventually opens into the tongue via the ____.
thyroglossal duct, pharynx, foramen cecum
The thyroglossal duct typically ____, but in rare cases remains and forms the ____ of the thyroid.
degrades, pyramidal lobe
A ____ occurs when the thyroglossal duct improperly or incompletely degrades. Sometimes it contains ectopic thyroid tissue.
thyroglossal duct cyst
The development of the tongue involves pharyngeal arches ____ to ____.
1 to 4
The ____ develops in the first pharyngeal arch as the beginning of the development of the tongue.
median lingual swelling
The median lingual swelling plays an inductive role in the formation of the ____.
lateral lingual swelling
The lateral lingual swelling gives rise to the ____.
anterior 2/3 of the tongue
In tongue formation, the 2nd pharyngeal arch gives rise to the ____ which eventually degrades, but plays an inductive role in the formation of the ____ from arches 3 & 4.
copula, hypopharyngeal eminence
In tongue formation, the 2nd pharyngeal arch also gives rise to the ____.
The hypopharyngeal eminence from pharyngeal arches 3 & 4 gives rise to the ____.
posterior 1/3 of the tongue
The median sulcus of the tongue is a remnant of ____.
the fusion of the lingual swellings
The terminal sulcus of the tongue is a remnant of ____.
the fusion between pharyngeal arch 1 and the hypopharyngeal eminence
The skeletal muscles of the tongue develop from ____, around week 5 of development.
The anterior 2/3 of the tongue gets somatosensory innervation from ____ and special sensory (taste) innervation from ____.
CN V(3), CN VII
The posterior 1/3 of the tongue gets somatosensory innervation from ____ and ____ and special sensory (taste) innervation from ____.
CN IX and X, CN IX
The muscles of the tongue get motor innervation from ____.
What are the 4 types of papillae on the tongue?
filiform, fungiform, folliate, and circumvallate
Which papillae of the tongue contain taste buds?
fungiform, folliate, and circumvallate
Taste buds relay special sensory (taste) information via ____ and ____.
CN VII and IX
Formation of the face begins as how many facial primordia around the stomodeum?
What are the 5 facial primordia?
Frontonasal Prominence (FNP), Paired Maxillary Prominences (MxP), and Paired Mandibular Prominences (MdP)
An ectodermal thickening, called the ____, forms on the FNP.
The mesenchyme below the nasal placodes proliferates and elevates up around the nasal placodes to form the ____.
The nasal placode invaginates into the underlying mesenchyme to form the ____ and dilates to become the ____.
nasal pit, nasal sac
Growth and enlargement of the ____ push the nasal prominences to the midline, forcing them to fuse.
Midline fusion of the nasal prominences gives rise to the ____ and ____.
bridge of the nose, intermaxillary segment
The intermaxillary segment gives rise to the ____, ____, and ____.
philtrum (of upper lip), upper jaw w/ 4 incisors, primary palate
The intermaxillary segment fuses with the ____ to allow fusion of the ____ and ____.
maxillary prominences, upper lip, palate
____ also fuse with the maxillary prominence, and incomplete fusion results in ____.
lateral nasal prominences, oblique cleft
____ forms at the site of fusion between the MxP and lateral nasal prominences, due to thickening and invagination of the ectoderm.
The two ____ fuse at the midline to form a single nasal cavity.
During development, the oral and nasal cavities are continuous due to the rupture of the ____.
Formation of the ____ ultimately separates the oral and nasal cavities.
____ develop from the lateral walls of the nasal cavity.
Cranial ectoderm in the nasal cavity differentiates to become the specialized ____.
The primary palate is derived from the ____.
The secondary palate is derived from the fusion of the ____.
The palatine shelves grow from the ____.
At about week 9, the growing mandible allows the tongue to drop down, leaving room for the ____ to fuse at the midline, and to fuse anteriorly with the ____.
palatine shelves, primary palate
Improper fusion of palatine shelves or of primary and secondary palate can result in ____.
____ is an autosomal dominant gene mutation in a protein involved in preribosomal processing. Symptoms include cleft palate, micronathia, conductive deafness, and deformed facial features. Results from neural crest defects in pharyngeal arches ___ and ___.
Treacher Collins Syndrome, 1 and 2
____ is characterized by micronathia, cleft palate, and susceptibility to respiratory distress syndrome at birth. It presents with heterogeneous birth defects with a range of severity.
Pierre Robin Syndrome
____ is caused by a ~30 gene deletion on chromosome 22. It presents with a wide range of complications and severity, and is due to neural crest defects in pharyngeal arches & pouches ___, ___, ___, and ___.
DiGeorge Syndrome, 1, 2, 3, 4
____ is the ectodermal origin of the teeth that develops in the mandible and maxilla.
Dental lamina invaginates to form ____, which invaginate into themselves to form a cap around the condensing ____.
dental buds, dental papilla
The dental papilla is mesenchyme derived from ____.
neural crest cells
Each jaw (upper and lower) develops how many dental buds?
The dental papilla (mesenchyme) differentiate into ____, which give rise to ____.
The outer epithelial/ectodermal dental cells differentiate into ____, which give rise to ____.