Pharyngeal arch Flashcards
What type of pouches grow from the pharynx?
Endodermal pouch
What forms a pharyngeal arch?
Mesodermal swelling
From which germ layer are pharyngeal arches formed?
Mesoderm
How do endodermal pouches cause pharyngeal arches?
Endodermal pouches grow out of th redeveloping pharynx towards the epidermis, this pushes against the mesoderm which swells forming a pharyngeal arch
What CN enter pharyngeal arch I?
V2 and V3
What are the muscular derivatives of pharyngeal arch I?
Muscles of mastication, levator veli palatine, tensor veli palatine, anterior digastric, mylohyoid
What CN enter pharyngeal arch II?
VII
What are the muscular derivatives of pharyngeal arch II?
Muscles of facial expression, posterior digastric, stylohyoid and stapedius
What nerve connects pharyngeal arch I and II?
Chorda tympani
What CN enters pharyngeal arch III?
IX
What are the muscular derivatives of pharyngeal arch III?
Stylopharyngeus
What CN enters pharyngeal arch IV/VI?
X and XI
What are the muscular derivatives of pharyngeal arch IV?
Muscles of pharynx larynx and soft palate
Which pharyngeal arch does V innervate?
I
Which pharyngeal arch does VII innervate?
II
Which pharyngeal arch does IX innervate?
III
Which pharyngeal arch does X innervate?
IV
Which pharyngeal arch does XI innervate?
VI
From which pharyngeal arch is the pharynx, larynx and soft palate derived?
IV/VI
From which pharyngeal arch is the muscles of mastication derived?
I
From which pharyngeal arch is mylohyoid, anterior digastric, levator veli palatine and tensor veli palatine derived?
I
From which pharyngeal arch are muscles of facial expression derived?
II
From which pharyngeal arch is stapedius derived?
II
What are the skeletal derivatives of pharyngeal arch I?
Maxillary and mandibular processes and malleus and incus
What are the skeletal derivatives of pharyngeal arch II?
Stapes, upper part of body of hyoid, lesser Cornu of hyoid, styloid process, stylohyoid ligament
What are the skeletal derivatives of pharyngeal arch III?
Greater Cornu of hyoid, lower part of body of hyoid
What are the skeletal derivatives of pharyngeal arch IV?
Cartilage of larynx
What are the derivatives of pouch 1?
Tubotympanic recess, external auditory meatus (middle ear)
What are the derivatives of pouch 2?
Palatine tonsil
What are the derivatives of pouch 3?
Inferior parathyroid gland
What are the derivatives of pouch 4?
Superior parathyroid gland and C cells of thyroid gland
