Flashcards in Sievert-Head and Neck Development and Superficial Face Anatomy Deck (161):
What are the three primordia of head and neck development?
pharyngeal/branchial arches (clefts and pouches)
What is this:
an ectodermal thickening that forms structures for some of our special senses
What are the types of placodes?
What do preotic somites turn into?
what do postotic somites turn into?
What is the nasal placode induced by?
adjacent olfactory bulb of the forebrain
What does the nasal placode form?
the primary olfactory epithelium (i.e cell of smell)
So you have the olfactory bulb which makes the nasal placode which forms the primary olfactory epithelium which then pierces what?
the olfactory bulb through the ethmoid bone (cribiform plane)
What does the olfactory bulb have within it that connects with primary neurosensory cells?
secondary neurosensory cells
How does the lens placode form?
the optic cup (neuroectoderm from diencephalon) induces a thickening of the surface ectoderm which forms the lens placode. (i.e the optic cup pac mans the ectoderm to create a lens)
Does the lens placode contain sensory cells?
What are the three parts to the ear?
external, middle and inner ear
What does the otic placode make?
the inner ear
(labryrinth and sensory neurons of cranial nerve 8)
What sensory neurons are made from the otic placode of cranial nerve 8?
What is the membranous labyrinth of the otic placode of cranial nerve 8?
utricle, semicircular canal, endolymphatic duct
What is significant about the development of the inner ear and why is this worrisome?
it is very slow
makes it susceptible to environmental defects
Cranial nerves that carry sensory info will have a cranial nerve ganglion (blank) the CNS where there would be no synpase present.
What becomes the future middle ear?
the pharyngeal pouch lined by the endoderm of the pharynx
What becomes the external ear?
the surface ectoderm of the first pharyngeal cleft (groove)
How does the tympanic membrane form?
three germ layers endoderm, mesenchyme, ectoderm meet up and form the tympanic membrane : )
What are masses of mesoderm that form skeletal muscles?
(blank) somites from muscles that move the eye not the muscles of the iris or the lens.
(blank) somites form muscles of the tongue
What are extraocular muscles?
muscles outside the eyeball that move the eyeballe (i.e. levator ptosis)
What CN take care of all extraocular eye muscles?
What are fibers that innervate muscles that came from somites?
general somatic efferents
What are the fibers that innervate muscles that are associated with viscera?
general visceral efferents
Whats another name for pharyngeal arches?
What are the fibers that innervate muscles that come from branchial arch of mesenchyme (no different than skeletal muscle)?
branchial motor efferents
What cranial nerve are used for extraocular muscles?
What cranial nerves are used for ear?
Masses of mesenchyme tissue that flank the developing gut appear around the (blank-blank) week.
Pharyngeal arches appear in (blank) to (blank) direction.
cranial to caudal direction
Each pharyngeal arches is associated with what three things?
artery, nerve, and bony structure
Describe the germ cell lining of a pharyngeal arch
ectoderm on outside, endoderm on inside, neural crests cells in bony structures
(blank) cells exist in the core of pharyngeal arches to contribute to skeletal components of the face.
Clefts are on the (blank) while pouches are on the (blank)
What four things will pharyngeal arches create?
skin from overlying ectoderm
lining of the gut from the lining endoderm
What does the maxillary process (from first arch) form?
the maxilla, zygomatic bone and part of the temporal bone.
Which arch forms the upper and lower jaws?
What all does mandibular process form?
the mandible, malleus, and incus
What skeletal element does the second arch form?
the hyoid arch froms the lesser horn of hyoid bone, styloid process and stapes
What skeletal element does the third arch form?
the rest of the hyoid bone that the second arch did not complete
What skeletal element does the fourth arch form?
nothing alone but with the 6th it fuses to form laryngeal cartilgae
What skeletal element does the first arch form?
maxillary process (maxilla, zygomatic bone, temporal bone) and mandibular process (mandible, malleus, and incus)
What kind of muscles does the first pharyngeal arch create?
muscles of mastication
What kind of muscles does the 2nd pharyngeal arch create?
muscles of facial expression
What kind of muscles does the 4th/6th pharyngeal arch create?
muscles of the pharynx, larynx, and palate
The (blank) lining each pharyngeal arch is innervated by the nerve of that arch
Which nerve innervates the first pharyngeal arch?
cranial nerve 5
On the anterior 2/3rds of the tongue, what happens to the the second arch? What does this mean about its nerve innervation?
it gets overgrow by arch 1 and thus is innervated by cranial nerve 5
Which nerve innervates arch 3?
glossopharyngeal (CN 9)
Which nerve innervates arch 4?
vagus and superior laryngeal nerve
Which nerve innervates arch 6?
vagus and recurrent laryngeal
What type of germ layer is the anterior 2/3rds of the tongue made up of?
What type of germ layer is the posterior 1/3 of the tongue made up of?
What arch gives sensory innervation to the epiglottis?
What arch gives sensory innervation to the root of the tongue?
What arch gives sensory innervation to the body of the tongue?
What separates the anterior tongue from the posterior tongue?
The first pouch merges with the first cleft to make the (blank).
auditory tube /eustachian tube and middle ear cavity
What does the second pouch make?
the palantine tonsil
What does the third pouch give rise to?
the inferior parathryoid gland to the thymus
What does the fourth pouch give rise to?
the superior parathyroid gland
What does the fifth pouch give rise to?
C cell of the thyroid gland
What cranial nerve goes to the nasal placode?
Is this motor or sensory?
cranial nerve 1 (sensory, special visceral afferents)
What cranial nerve goes to the optic placode?
Cranial nerve 2 (sensory, special somatic afferent)
What cranial nerves goes to the preotic somites?
CN 3,4,6 (motor, give rise to extraocular eye muscles)
What cranial nerve innervates arch 1 and is used for muscles of mastication?
CN 5 (trigeminal nerve)
What cranial nerve innervates the second arch and gives motor innervation to the face?
CN 7 (fascial)
What cranial nerve innervates the otic placode (vesicle) and is used in balance and hearing?
CN 8 (vesitbulocochlear) (special somatic afferents)
What cranial nerve innervates the third arch?
CN 9 (glossopharyngeal)
What cranial nerve innervates the fourth arch, sixth arch and the muscles of the pharynx, larynx, and palate?
CN 10 (vagus)
What cranial nerve innervates the post otic somtimes?
cranial nerve 12 (hypoglossal) i.e. tongue movement
Which CN go to placodes?
I, II, VIII
Which CN go to somites?
III, IV, VI, XII (somatomotor nerves)
Which CN go to branchial arches?
V, VII, IX, X (branchiomotor nerves)
What are the four different things that a spinal nerve may contain?
general sensory (GSA), viscerosensory (GVA), somatomotor (GSE), visceromotor (GVE)
The (blank) plate gives rise to sensory cell bodies. The (blank) plate gives rise to motor cell bodies.
Where do you find the visceromotor cell bodies of sympathetics?
S2-4 and CN 3,7,9,10
Vision and balance/ hearing travel on which kinds of nerves?
special somatosensory (SSA)
Sounds like NSA (they can hear and see you )
Taste buds and nasal placodes travel on which kinds of nerves?
special viscerosensory (SVA)
All motor neurons of cranial nerves are in the (blank)
Cell bodies of nuclei are (blank)
All sensory neurons (1st order) of cranial nerves (blank-blank) are in ganglia except the proprioceptive fibers for the face.
What 2 cranial nerves do not have all their sensory neurons in ganglia?
CN I and CN II
The brainstem undergoes alteration in shape due to a big space called the (blank)
Where do you find the nuclei of cranial nerves 5, 6, 7, and 8?
in the pons
Where do you find the nuclei of cranial nerves 3,4?
Where do you find the nuclei of cranial nerves 9, 10, 11, 12?
What is the most lateral column of the brainstem in the alar plate? Now name them from lateral to medial.
general somatosensory> general and special visceral afferent
What is the most lateral column of the brainstem in the basal plate? now name them from lateral to medial?
visceromotor> branchiomotor> somatomotor
How can you recognize the medulla?
What cranial nerves are somatomotor?
3,4,6, and 12
What cranial nerves are visceromotor?
3,7,9, and 10
What cranial nerves are branchiomotor?
What cranial nerves are special sensory?
What cranial nerves are general sensory?
What cranial nerves are visceral sensory?
9 and 10
What cranial nerves are including taste?
7, 9,and 10
DO nerves ever carry both somatomotor and branchiomotor?
Where do you get the majority of your sensory innervation to your head? Where does the rest of it come from?
from cranial nerve 5
cervical plexus (ventral rami), greater occipital (dorsal rami of cervical spinal nerves)
What are the three division of the trigeminal nerve?
opthalamic division (V1)
maxillary division (V2)
mandibular division (V3)
What is the terminal branch of the opthalmic nerve (V1) that comes out of the supraorbital foramen of the skull?
Does CN 5 carry any sympathetics back to the brainstem?
Why do the parasympathetics and sympathetics jump on CN 5?
because it goes everywhere in the head.
What is the terminal branch of the maxillary nerve (V2) and what foramen does it go through?
What is the terminal branch of the mandibular nerve (V3) and what foramen does it go through?
WHat makes up the brainstem and what does it look like?
the midbrain, pons, medulla
How do the cranial nerves exit the brain stem?
they all leave ventrally except for cranial nerve 4 (trochlear nerve)
What kind of neuron leave the spinal cord and sends its axon directly to muscle.
lower motor neuron
Lower motor neuron only respond to 2 things, what are they?
afferents and or descending signals from above
(blank) regulate local circuits in the spinal cord and brainstem that coordinate individual muscle groups, thus enabling and coordinating complex
sequences of movements and ensuring appropriate autonomic activity in support of the behavioral needs at hand. These connect the brain to the spinal cord by carrying motor innervation to lower motor neurons.
upper motor neurons
What is a mass of cells whose axons form the middle cerebellar peduncle?
pontine gray of the caudal pons
In the midbrain, the corticospinal, corticobulbar and corticopontine fibers are collected into a bundle known as the (blank), giving the midbrain an easily recognizable look.
Where does CN 5,6,7,8 exit the brain stem?
5 ,6 ,7, 8 who do we appreciate PONS PONS!
Where does CN 9-12 exit the brain stem?
Where do CN 3 and 4 exit the brain stem?
Where is the nucleus of cranial nerve V?
the brainstem where the ganglion cells dump off their info
From which pharyngeal arch do we get the muscles of facial expression?
pharyngeal arch 2
Where do the muscles of facial expression insert?
into the skin
Besides producing facial expressions, what else do the muscles of facial expression do?
they protect the face (eye)
What are the 7 facial expression muscles?
What are these innervated by?
What is the deepest muscle in your face near the mouth?
What are the 5 terminal branches of CN 7? What do these do?
innervate the muscles of facial expression
(ten zebras block my car)
What is paralysis of the facial nerve, causing muscular weakness in one side of the face?
What does CN 7 exit the skill through and what kind of fibers are on it?
motor (it lost everything else inside the skull or middle ear)
If you had a lesion at the styloidmastoid foramen, (i.e) what would be the lesion?
a lower motor neuron lesion
Where is the facial motor nucleus?
in the branchiomotor column
Explain how the facial motor neuron axons exit the brain stem
they travel over the abducens nucleus and exit on the facial nerve from the caudal pons
What is significant about the facial nerve?
it has a convoluted path so it can be damaged at different places and affect or spare different components.
As the facial nerve leaves the stylomastoid foramen what is left on it?
What are the two superficial arterial branches?
external carotid artery
internal carotid artery (via opthalmic artery)
What are the 2 branches off the external carotid?
What are the 2 branches off the internal carotid?
What do you find between the external carotid and internal carotid?
Tell me the layers of the scalp from external to internal?
Dense CT (holds arteries tight)
What all is considered the scalp proper?
skin, CT, aponeurosis
Numerous arteries anastomose in the (blank) layer. What is signif. about this layer?
What part of the scalp is considered the danger space? Why is it dangerous?
the loose connective tissue layer
spread of infection occurs here
What are the three thin and pliable bones of the skull of a newborn?
What are the three sutures of the newborn skull?
What are the 2 fontanels of the newborn?
anterior and posterior
What do you call premature suture closure? How often does this happen?
1/2500 births and found in greater than 100 genetic syndromes
What are two types of craniosynostosis? What sutures are involved?
brachycephaly (flat head) and oxycephaly (cone head)
coronal and lambdoid sutures
What are the bones of the neurocranium?
What do you call the point where the coronal and sagittal sutures meet?
What do you call the point where the lambdoid and the sagittal sutures meet?
What are the four nuclei of the trigeminal nerve?
What column is the spinal nucleus in and what is its function?
general somatosensory column and gives you pain and temp. from face, head and ant. 2/3rds of the tongue
What column is the mesencephalic nucleus in and what is its function?
general somatosensory column and gives you unconscious proprioception
What column is the motor nucleus in and what is its function?
branchiomotor column and gives you innervation to the muscles of mastication, tensor tympani, tensor (veli) alatinin, mylohoid, and the ante. belly of digastric
What column is the chief sensory nucleus in and what is its function?
general somatosensory column and it gives you 2 pnt. discrimination and vibrational sense from face and head.
What are the foramen for that are on either side of the parietal bone?
foramen for emissary veins
Whats the groove in the center of the frontal bone for?
it is the groove for the superior sagittal sinus
What are the big divots in the parietal bone for?
they are foveolae granules
What are the branch like grooves that progress laterally to medially on the skull cap?
the grooves for the middle meningeal vessels
What CN innervates the palantine tonsil and posterior 1/3 of the tongue?
What CN innervates the anterior 2/3 of the tongue?
What CN innervates the epiglottis?
What does the scalp aponeurosis do?
connects frontalis muscle to the occiptalis muscle