Embryo of Pharyngeal Apparatus Flashcards
What is part of the pharyngeal apparatus?
Pharyngeal Arches
Pouches
Grooves (clefts)
Membranes
What does the pharyngeal apparatus contribute to the formation of?
Nasal cavities Mouth Larynx Pharynx Neck
The Pharyngeal Arches develop early in the 4th week as _______ _______ _______ migrate into the future head and neck.
Neural Crest Cells
The 1st pair of pharyngeal arches, the _______ _______, appear lateral to the developing pharynx.
Primordial Jaws
What type of embryonic cells make up the pharyngeal arches?
Externally = Surface ectoderm Internally = Endoderm Core = Mesoderm and Mesenchyme
What is mesenchyme derived from?
Migratory Neural Crest Cells
What is head mesoderm derived from?
Forms from Paraxial Mesoderm
This component of the Pharyngeal Arches forms all CT in the head, including the dermis (integument) and smooth muscle.
NCC-derived Mesenchyme
This Pharyngeal Arch component populates each arch to form musculature.
Paraxial Mesoderm
This component of the Pharyngeal Arch consists of angioblasts that differentiate into endothelium.
Lateral Plate Mesoderm
This component of the Pharyngeal Arch makes up extra ocular musculature (i.e., Orbicularis Oculi).
Prechordal Plate Mesoderm
What does Pharyngeal endoderm do?
Plays essential role in regulating development of the arches
What are the main structures of the Pharyngeal Arches?
1) Cartilaginous rod – forms skeletal elements
2) Muscular component – becomes muscles in head/neck
3) Cranial nerves – with sensory and/or motor
4) Arch artery
Where does the Arch Artery arise from?
Truncus Arteriosus of the primordial heart
What is the cartilage of PA 1?
Meckel’s Cartilage
What will develop from Meckel’s Cartilage (PA 1)?
Malleus Incus Mandible Sphenomandibular L. Anterior L. of Malleolus
What is the cartilage of PA 2?
Riechert’s Cartilage
What will develop from Riechert’s Cartilage (PA 2)?
Stapes
Styloid Process of Temporal bone
Stylohyoid L.
Lesser Cornu of Hyoid bone
What will develop from the PA 3 cartilage?
Greater Cornu of Hyoid bone
The body of the Hyoid bone is formed by the __________ __________. This is a prominence in the floor of the embryonic pharynx from PA 3 and PA 4.
Hypopharyngeal Eminence
What will develop from the PA 4 and PA 6 cartilages?
Laryngeal Cartilages (both) Epiglottis (PA 4 only)
What are the muscular components of the Pharyngeal Arches derived from?
Paraxial Mesoderm Prechordal Plate (extraocular muscles)
What muscular components come from PA 1?
ChewOnThat
Muscles of Mastication
What muscular components come from PA 2?
SmileAndSayCheese
Stapedius M.
Muscles of Facial Expression
What muscular components come from PA 3?
ElevateAndDilate
Stylopharyngeus M.
What muscular components come from PA 4?
PushItPushItRealGood
Cricothyroid M.
Levator Veli Palatini M.
Pharyngeal Constrictors
What muscular components come from PA 6?
SoundOff
Intrinsic muscles of the Larynx
What cranial nerves innervate the Pharyngeal Arches?
PA 1 – CN V
PA 2 – CN VII
PA 3 – CN IX
PA 4/6 – CN X