Development of Head and Neck. Flashcards
Pharyngeal arches - Derivation.
NCC migrating to Neck region. (Major)
Intraembryonic Mesoderm - Paraxial and Lateral Mesoderm.
When are Pharyngeal arches are formed.?
4th week.
Pharyngeal Clefts - Derived from
Outer ectoderm.
Pharyngeal Pouches - Derived from
Inner Endoderm.
Pharyngeal Membrane - contains.?
all three Germ layers.
1st membrane - Tympanic membrane.
Rest all obliterates.
Point where Cleft meets pouch -
Pharyngeal membrane.
Components of Pharyngeal arch.?
Cartilage, Muscles, Nerve, Artery.
Cartilage component of 1st arch -
Meckel’s cartilage, Malleus, Incus, maxilla, mandible, sphenoid, zygomatic, temporal bone.
Cartilage component of 2nd arch -
Richter’s cartilage - Stapes, Styloid, Stylohyoid, Supr surface of hyoid, Small horn of hyoid.
Cartilage component of 3rd arch -
Greater horn of hyoid, Infr surface of hyoid.
Cartilage component of 4th and 6th arch -
Cartilages of larynx excpt epiglottis.
Epiglottis - derived from
mesoderm of Hypobranchial eminence of 4th arch.
Muscle component of 1st arch
Muscles of mastication, Tensor tympani, Tensor palatini, Mylohyoid.
Nerve component of 1st arch -
Mandibular nerve.
Pre - Trematic- Chorda tympani nerve.
Artery component of 1st arch-
Maxillary artery.
Muscle component of 2nd arch -
Muscles of facial expression, Posterior belly of digastric.
stylohyoid, stapedius.
Nerve component of 2nd arch -
Facial nerve.
pre - trematic nerve - Tympanic nerve of IX
Artery component of 2nd arch -
Stapedial artery.
Mandibular branch of Arches is .?
1st arch
Hyoid branch of arches is .?
2nd arch
Cartilage component of 3rd arch .?
Greater horn of hyoid, inferior surface of hyoid.
Muscle component of 3rd arch.?
Stylopharyngeus.
Artery component of 3rd arch.?
CCA, ICA, ECA.
Nerve component of 3rd arch .?
Glossopharyngeal.
Cartilage component of 4th and 6th arch.?
Cartilage of larynx except epiglottis.
Muscle component of 4th arch.?
Muscle of pharynx (except - Stylopharyngeus) and plate and cricothyroid.
Muscles of Larynx is derived from 6th branch except
Cricothyroid.
Muscles of pharynx is derived from 4th branch except -
Stylopharyngeus.
Muscle component of 6th arch.?
Muscles of larynx except circothyroid.
Nerve component of 4th arch .?
SLN
Nerve component of 6th arch .?
RLN
Artery of 4th arch .?
Aortic arch, right subclavian artery.
Artery of 6th arch.?
Pulmonary artery and ductus arteriosus.
Aortic arch derived from
left 4 th arch.
Right subclavian artery derived from
right 4th arch.
Distal left 6th arch gives rise to which artery.?
Ductus arteriosus.
Hypobranchial eminence of 4th branch gives rise to
epiglottis and posterior most part of tongue.
Muscles of palate derived from 4th arch except.?
Tensor palatini - 1st arch.
Failure of differentiation of 1st arch derivatives
Treacher collins and Pierre robinson syndrome.
Treacher collins syndrome
Failure of differentiation of 1st arch derivatives.
Facial asymmetry, Coloboma of lower eyelid, External ear anomalies.