Term
What does the Pharyngeal Apparatus consist of? |
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Definition
Pharyngeal arches, pouches, grooves, and membranes |
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Term
How many pairs of pharyngeal arches? |
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Definition
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Term
By the end of the 4th week, how many visible pairs of pharyngeal arches? |
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Definition
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Term
What seperates pharyngeal arches? |
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Definition
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Term
mesenchyme of pharyngeal arches is derived from where? |
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Definition
Depends
Third week: paraxial and prechordal
fourth week: replaced by neural crest mesenchyme |
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Term
What are the layers of a pharyngeal arch? |
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Definition
Mesenchyme core covered externally by ectoderm and internally by endoderm |
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Term
The two prominences (mandibular and maxillary) derive from what pharyngeal arch? |
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Definition
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Term
The 1st pharyngeal cartiledge is named what? What does it give rise too? |
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Definition
Meckel's Cartiledge:
dorsal end gives rise to the malleus and incus
middle part gives rise to the anterior ligament of the malleus and the sphenomandibular ligament
ventral part forms primordium of mandible |
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Term
What is the name of the second pharyngeal cartilage? What does it give rise too? |
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Definition
Reichert's cartilage:
Dorsal end gives rise to the stapes and styloid process of temporal bone
middle gives rise to the stylohyoid ligament
ventral end gives rise to the lesser cornu and superior part of the body of the hyoid bone |
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Term
How is the cervical sinus formed? |
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Definition
during the 5th week the 2 pharyngeal arch engulfs the third and fourth pharyngeal arch forming the cervical sinus |
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Term
Why does the second pharyngeal arch grow to engulf the third and fourth arches? |
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Definition
Second pharyngeal arch has a signalling center that responds to SHH, FGF-8, and BMP-7 |
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Term
What does the third pharyngeal arch cartilage give rise too? |
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Definition
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Term
What do the 4th and 6th pharyngeal cartilages give rise too? |
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Definition
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Term
What muscles and enervation derive from the first pharyngeal arch? |
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Definition
Nerve: Trigeminal
Muscles: Muscles of Mastication
Mylohyoid and anterior belly of the digastric
Tensor Tympani
Tensor Veli Palatini |
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Term
What muscles and enervation derive from the second pharyngeal arch? |
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Definition
Nerve: Facial Nerve
Muscles: Muscles of Facial Expression
Stapedius
Stylohyoid and Posterior belly of the digastric |
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Term
What muscles and enervation derive from the 3rd pharyngeal arch? |
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Definition
Nerve: Glossopharyngeal
Muscles: Stylopharyngeus |
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Term
What muscles and enervation derive from the 4th pharyngeal arch? |
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Definition
Nerve: Vagus (external laryngeal)
Muscles Cricothyroid
Muscles of soft palate except Tensor veli palatini
constrictors of pharynx |
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Term
What muscles and enervation derive from the 6th pharyngeal arch? |
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Definition
Nerve: Vagus (laryngeal recurrent)
Muscles: intrinsic muscles of larynx (except cricothyroid) |
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Term
Which pharyngeal arch arteries disappear? |
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Definition
First, second, fifth, and the right side of sixth |
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Term
The third pharyngeal arch artery eventually becomes what? |
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Definition
Common carotid and the proximal part of external carotid |
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Term
The fourth pharyngeal arch artery eventually becomes what? |
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Definition
small part of the subclavian and small part of the arch of the aorta |
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Term
The sixth pharyngeal arch artery eventually becomes what? |
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Definition
proximal portion of pulmonary artery ductus arteriosis |
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Term
The sixth pharyngeal arch artery eventually becomes what? |
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Definition
proximal portion of pulmonary artery ductus arteriosis |
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Term
What is the ductus arteriosis? |
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Definition
prenatal shunt that allows the blood to circumvent the fluid filled (and useless) fetal lungs |
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Term
Why does the vagus recurrent loop around the subclavian vein and not a growth of the sixth pharyngeal arch artery? |
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Definition
The right side of the sixth pharyngeal arch artery disappears |
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Term
What are the derivatives of the first pharyngeal arch artery? |
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Definition
Terminal branch of maxillary artery (infraorbital) |
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Term
What are the derivatives of the second pharyngeal arch artery? |
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Definition
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Term
What are pharyngeal pouches? |
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Definition
endoderm that defines internal divisions of the pharyngeal arches. Functional internal analogs to the pharyngeal grooves |
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Term
What does the first pharyngeal pouch develop into? |
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Definition
internal structures associated with the ear.
tympanic cavity, mastoid antrum, auditory (eustachian) tube |
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Term
What does the second pharyngeal pouch develop into? |
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Definition
mostly displaced by palantine tonsils but remnant remains as tonsillar sinus |
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Term
What does the third pharyngeal pouch develop into? |
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Definition
two areas
dorsally develops into the inferior parathyroid glands
ventrally develops into the thymus |
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Term
What does the fourth pharyngeal pouch develop into? |
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Definition
Dorsally develops into the superior parathyroid glands
Ventrally develops into the postbrachial body (ultimobrachial body) |
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Term
What is the cellular origin of the postbrachial body (ultimobrachial body) |
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Definition
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Term
What does the postbrachial (ultimobrachial) body eventually differentiate into? |
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Definition
The c-cells of the thyroid (parafollicular cells)
secrete calcitonin |
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Term
How many pharyngeal grooves persist? |
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Definition
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Term
What does the first pharyngeal groove differentiate into? |
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Definition
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Term
What are the possible complications from a persistant pouch? |
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Definition
Branchial sinuses, fistulas, cysts, or vestiges
if persistant sinus breaks skin then it is a fistula
if it goes through but does not break skin it is a cyst |
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Term
Where are persistant pharyngeal pouch congenital anomalies typically found? |
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Definition
Just anterior to sternocleidomastoid |
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Term
What are first arch syndromes associated with failure of neural crest migration? |
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Definition
Treacher Collins Syndrome
Pierre Robin Syndrome |
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Term
What are the symptoms of Treacher Collin's syndrome? |
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Definition
Malar hypoplasia Downslanting palpebral fissures Defects in lower eyelids deformed external ears |
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Term
What are the symptoms of Pierre Robin Syndrome? |
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Definition
Hypoplasia of the mandible Cleft palate Defects in eyes and ears |
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Term
What is the pharyngeal pouch syndrome associated with failure to differentiate in the third and fourth pouch? |
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Definition
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Term
What are the symptoms of DiGeorge syndrome? |
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Definition
Congenital thymic aplasia abnormalities of the mouth low set ears nasal clefts Thyroid hypoplasia Cardiac abnormalities |
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Term
What causes the failure of differentiation in DiGeorge Syndrome? |
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Definition
Microdeletion of q11.2 of Chromosome 22 |
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Term
What causes accessory thymic tissue or parathyroid glands to form? |
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Definition
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Term
What is the first endocrine gland to develop in the embryo? |
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Definition
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Term
What is the composition of the thyroid gland? |
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Definition
solid mass of endodermal cells that are then invaded by vascular mesenchyme |
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Term
Initially the thyroid gland is connected to the foramen cecum via what structure? |
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Definition
The thyroglossal duct
if it persists it can form a cyst |
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Term
How do the inferior parathyroid glands make it below the superior parathyroid glands when they are formed in a superior pouch? |
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Definition
By traveling with the thymus |
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Term
What is the pyramidal lobe? |
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Definition
persistant tissue of thyroid. Forms a third lobe that can reach as high as the hyoid bone |
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Term
Where would a thyroglossal duct cyst be most commonly found? |
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Definition
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Term
What is the sulcus terminale of the tongue? |
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Definition
Divides the anterior 2/3 and posterior 1/3 of the tongue |
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Term
What provide motor enervation to the tongue? |
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Definition
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Term
Tongue musculature developes from what myoblasts? |
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Definition
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Term
Where does the anterior 2/3 of the tongue develop? |
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Definition
1st pharyngeal arch
develope as lateral lingual swellings that overgrow the median tongue bud |
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Term
Where does the Copula develop? |
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Definition
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Term
Where does the hypopharyngeal eminence form? |
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Definition
3rd and 4th pharyngeal arch |
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Term
How does the posterior 1/3 of the tongue develop? |
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Definition
Hypopharyngeal eminence grows over the copula |
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Term
What nerve provides sensory enervation to the anterior 2/3 of the tongue? |
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Definition
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Term
What nerve provides taste to the anterior 2/3 of the tongue? |
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Definition
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Term
What nerve provides sensory ennervation to the posterior 1/3 of the tongue? |
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Definition
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Term
What nerve provides taste to the posterior 1/3 of the tongue? |
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Definition
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Term
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Definition
Anomaly of tongue development, typically a remnant of the thyroglossal duct |
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Term
What anomaly is associated with a short lingual frenulum? |
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Definition
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Term
What is the name for an unusually large tongue? |
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Definition
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Term
What is the name for an unusually small tongue? |
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Definition
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Term
From what cell is the anterior pituitary derived? |
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Definition
Anterior portion is ectoderm
posterior portion is neuroectoderm |
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Term
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Definition
anterior portion of anterior pituitary. Derived from ectoderm |
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