Embroyology- The Pahryngeal Arches Flashcards
What are the pharyngeal arches?
A system of menechyme proliferations in the head and neck region
What are the numbers of the pharyngeal arches?
Numbered 1-6 but there is no number 5 in humans
What are the cranial nerves of the pharyngeal arches?
CNV, CVII, CNIX and CNX
From where is the facial skelton derivied?
The frontonasal prominence and the 1st pharyngeal arch
From where are the muscles of mastication derivied?
The 1st pharyngeal arch
From where are the muscles of facial expression dervived?
The second pharyngeal arch
What muscles are derived from the third pharyngeal arch?
The stlyopharyngeus
What muscles are derivied from the 4h pharyngeal arch?
The cricothryoid, the levator plantani and the constrictors of the pharynx
What is the cranial nerve of the 1st arch?
CNV the trigemnial nerve
With what pharyngeal arch is the facial nerve assoicated with?
The 2nd pharyngeal arch
What is the nerve of the third pahryngeal arch?
The glossopharyngeal nerve CNIX
With what pahryngeal arches is the vagus nerve associated?
The 4th and 6th pharyngeal arches
What are the branches of the vagus nerve that are associated with different pharyngeal arches?
The 4th arch branch is the superior laryngeal nerve
The 6th arch branch is the recurrent laryngeal nerve
What is the cartilage associated with the 1st pahryngeal arch?
Meckels cartilage
What cariltganous structures does the 1st pharyngeal arch help to create?
Divides into maxillary and mandibular prominences, mandibular prominence helps develop to the prominent meckels cartilage which helps to form the malleus and the incus by membranous ossification
What is the caritalge that is assoicated with the second pahryngeal arch?
Reicherts cartilage
What bony structures do the second pahryngeal arch contribute towards the development of?
Middle ear development, the stapes, the sytolid proccess of the temporal bone, the stylohyoid ligament and the upper body the hyoid bone ( remainder is dervived from the third arch of the cartilage)
What are some of the derviatives of the third pahryngeal arch?
The cartilage produces the lower part of the body of the hyoid boen
What bony structures do the 4th and 6th arc cartilages contribute to the development of?
The mesenchyme of the pharyngeal floor helps to form the epiglottis, and the cartilaginous components of the 4th and 6th pahryngeal arches fuse to form the hyoid
What arieries are formed from the 1st and 2nd pahryngeal arches?
None, the ateries associated with these disappear
What are the ateries dervived from the 3rd branch of the pahryngeal arch?
The internal cartoid artery
What are the arteries associated with the 4th arch atery?
Arch of aorta, and the barhcepatlis artery
What are the arteries associated with the 6th pharyngeal arch?
Pulmonary arch
What is formed by the first pharyngeal pouch?
The future external aurdoitory meatus, and helps to form the primitive middle ear cavity
What are some of the deriviatives of the secon pharyngeal pouch?
Help to form the primodium of the palatine tonsils, as they are infiltrated by lymphoid tissues
What are some of the derviatives of the third pahryngeal pouch?
The ventral region of the third pouch helps to from the thymus
The dorsal region of the 3rd and 4th puches help to form the parathryod tissue
What are some of the derviatives of the fourth phayrngeal pouch?
Eptihelium of the dorsal region forms the 4th pahryngeal puch,
What happens to the pharyngeal clefts?
The 1st celft is all that remains, and the 2nd arch grows down to cover them and obliaterate all the other clefts
What happens if the cercival sinus is not obliterated?
Cysts or fistulae can occur, can occur anywhere down the anterior border of the sternocleiodmastoid, are are most often below the angle of the jaw