Quiz 1 - Moore - Pharyngeal Arches Flashcards
What does branchial mean?
Gills
What would have a greater impact on the organism, a disruption during the formation of the pharyngeal system or a disruption during development of pharyngeal derivatives?
Pharyngeal system
*This is earlier on in the cycle, and can impact more things down the road
DISRUPTIONS TO EITHER PHASE CAN RESULT IN A BROAD SPECTRUM OF DEFECTS
Name 3 syndromes associated with problems in the 1st arch.
Treacher-Collins
Pierre Robin
DiGeorge Syndrome
What is a cyst?
Sealed cavity filled with air, pus, fluid
What is a sinus?
Cavity w/in a tissue, can open externally
What is a fistula?
Abnormal connection b/t 2 structures
- B/t 2 epithelialization surfaces
- Usually b/t 2 hollow structures
- Blind: Open on one end only
- Complete: Openings inside and outside body
- Incomplete: Tube from skin closed on inside, no internal connection
Define migration.
Cells move, or not, during development
Define proliferation.
Growth in cell number thru cell division
Define genetics.
Mutations change patterns in migration, proliferation, etc.
Where do pharyngeal arches emerge at?
Neural tube closure
*Ectodermal pouches filled with mesenchyme
**1st arch is of primary relevance to the face
Which arch shows 2 prominences clearly, and what are the prominences?
1st arch
*Maxillary and mandibular prominences
Ecto
Meso
Endo
Neural crest
Outside
Middle
Inside
Middle (Either from Ecto or meso)
What are the 4 components of pharyngeal arches?
Aortic arch - artery that arises from the truncus arteriosus of the primordial heart, bridge b/t the truncus arteriosus and dorsal aorta, ARISES FROM MESODERM
Cartilaginous rod - Forms the skeleton of the arch
Muscular component - Differentiates into mm in the head and neck
Nerve - Supplies mucosa and mm derived from the arch
Aortic arches 1 and 2 do what?
Largely disappear, but the remains are maxillary, ext carotid, stapedial
Aortic arches 3,4, and 6 do what?
Remodeled to form portions of some large arteries - common and int carotid (3), aortic, subclavian (4), pulmonary (6)
What arch mesoderm gives rise to facial bones?
Arch 1
What are some structures formed by the cartilaginous components of the arches?
Malleus, incus, stapes, styloid process, hyoid, thyroid cartilage, cricoid cartilage
Endochondral ossification comes from where?
Direct from cartilage
Intramembranous ossification comes from where?
Direct from mesoderm
*Arch 1 gives rise to facial bones (temporal, zygomatic, maxilla, mandible)
Muscles come from where?
Mesoderm of the individual arches
Muscles:
Arch 1? Arch 2? Arch 3? Arch 4? Arches 5-6?
MFSPL - My Fleury Sexy PLace
1 - Mastication 2 - Facial 3 - Stylopharyngeus 4 - Pharyngeal constrictors 5-6 - 5 disappears, 6 - Laryngeal mm
Cranial nerves contain ______ nerves (________ ________ and __________ placode derived) and _________ nerves (CNS derived)
Sensory
Neural crest
Ectodermal
Motor
Arch 1 is associated with what CN?
V
*Maxillary prominence associates with V2
**Mandibular prominence associates with V3
What muscles are associated with arch 1?
Mastication (Temporalis, masseter, med and lat pterygoids)
Mylohyoid
Ant digastric
Tensor palatine
Tensor tympani
What parts of the skeleton are associated with arch 1?
Meckel’s cartilage
Maxilla
Mandible
Malleus
Incus
Zygomatic bone and process
Temporal bone
Vomer
Palatine bone
Arch 2 is associated with what CN?
Facial
Arch 2 is associated with what muscles?
Facial expression
Post digastric
Stylohyoid
Stapedius
Platysma
Arch 2 is associated with what parts of the skeleton?
Stapes
Styloid process
Stylohyoid ligament
Lesser horn and upper portion of body of hyoid
Arch 3 is associated with what CN?
Glossopharyngeal
Arch 3 is associated with what muscle?
Stylopharyngeus
Arch 3 is associated with what parts of the skeleton?
Greater horn and lower portion of body of hyoid
Arch 4 is associated with what CN and what specific nerve?
Vagus
-Superior laryngeal
Arch 4 is associated with what muscles?
Cricothyroid
Pharyngeal constrictors
Levator veli palatini
Arch 4 is associated with what part of the skeleton?
Laryngeal cartilages
Arch 6 is associated with what CN, and what specific nerve?
Vagus
-Recurrent laryngeal
Arch 6 is associated with what muscles?
Intrinsic muscles of larynx, EXCEPT CRICOTHYROID
The mandibular process of Arch 1 forms what?
Lower lip, face, and cheek regions, chin, mandible, body of tongue
The maxillary process of Arch 1 forms what?
Midface, upper cheek regions, upper lip sides, secondary palate, maxilla, zygomatic bone
Failure of the neural crest to properly migrate into 1st arch results in what syndrome?
First Arch Syndrome
- Treacher-Collins syndrome - hypoplasia of arch derived facial bones
- Pierre Robin Syndrome - hypoplasia of the mandible
How many pharyngeal grooves/clefts are there?
4
Which cleft is the only cleft normally NOT obliterated in development?
Cleft 1
*Clefts 2-4 can persist in ABNORMAL situations
Clefts are lined with what development layer?
ECTODERM!
What does cleft 1 give rise to?
External auditory meatus
What are congenital auricular sinuses and cysts?
Small pits (sinuses) and cysts commonly found in a triangle of skin anterior to the ear
*May be a remnant of the pharyngeal groove/cleft [Which one?]{Cleft 1!}
**Largely irrelevant. No significance unless it opens deep in the tissue
Lateral cervical pharyngeal cleft anomalies?
Uncommon, open EXTERNALLY - failure of 2nd groove or cervical sinus to obliterate
*Ant border of SCM from tragus to clavicle
Internal branchial pharyngeal cleft anomaly?
Rare, persistent second pouch - opens into INTRA-TONSILLAR CLEFT (Pharynx)
