GI Anatomy Flashcards
What are the three types of innervation to the tongue?
What are the four extrinsic muscles and four intrinsic muscles of the tongue?
Extrinsic Muscles: Palatoglossus, Styloglossus, Hyoglossus, Genioglossus.
Intrinsic Muscles: Transverse, Superior longitudinal, Inferior longitudinal, Vertical.
Explain the motor innervation of the tongue.
Vagus nerve - Innervates the palatoglossus muscle.
Hypoglossal nerve - innervates all 7 other muscles of the tongue.
What papilla are central to the tongue?
Filiform papillae - do not taste.
Why do the oral and pharyngeal parts of the tongue have different innervation?
Oral and pharyngeal parts have different innervation because they arise from different pharyngeal arches.
Oral part = anterior 2/3 before terminal sulcus.
Pharyngeal part = posterior 1/3 after terminal sulcus.
What nerve provides general sensation to the tongue?
- what is this a branch of?
Lingual nerve
- a branch of the Mandibular nerve CN V3
What nerves provides taste sensation to the tongue?
- what is this a branch of?
Chorda tympani
- Branch of the facial nerve CN VII
What nerve gives both taste sensation and general sensation to the posterior pharyngeal part of the tongue?
Glossopharyngeal nerve.
What are the major salivary glands?
Parotid
Submandibular
Sublingual
Where are the minor salivary glands found?
Throughout the oral mucosa.
Para-otid
Para-otid = next to ear
Explain the secretomotor nerve supply to the parotid gland.
• Originates in glossopharyngeal nerve - synapses in otic ganglion. Then carried to gland in auriculotemporal nerve.
Explain the secretomotor nerve supply to the submandibular gland.
Innervation from chorda tympani (cn. VII) - carried in lingual nerve.
Explain the secretomotor nerve supply to the sublingual gland.
Innervation from chorda tympani (cn. VII) - carried in lingual nerve.
Is the innervation to the salivary glands sympathetic or parasympathetic?
Parasympathetic - as not under conscious control.
Summary of innervation to the salivary glands:
What nerve passes through the parotid gland but does not supply it?
- Important in a parotidectomy.
Facial nerve
What are the muscles of mastication?
Temporalis
Lateral pterygoid
Medial pterygoid
Masseter
How does the temporalis move the mandible?
Anterior fibres elevate the mandible.
Posterior fibres retract the mandible.
How does the masseter move the mandible?
Elevates the mandible.
How does the medial pterygoid move the mandible?
Elevates the mandible
How do the laterl pterygoids move the mandible?
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