Upper Gastrointestinal Tract Flashcards
What structure is the oral cavity continuous with?
Pharynx
What is the oral cavity divided into?
Oral vestibule- behind the lips, continuous with oral cavity proper
Oral cavity proper- median to teeth
What circular muscle surrounds orifice of mouth?
Orbicularis oris - helps out lips
What muscle is lateral to the orbicularis oris?
Buccinator muscle - helps blow out cheeks
Where is saliva produced/
Parotid gland
Why is buccinator muscle an important landmark?
Parotid duct transports saliva over masseter muscle to enter into oral cavity by travelling through buccinator muscle
What does the floor of the oral cavity consist of?
Mylohyoid muscle (superficial) runs from mandible to hyoid bone (floating bone)
Geniohyoid muscle (superior to mylohyoid)
What forms the roof of the oral cavity?
Hard palate (bone- roof of mouth) Soft palate (posterior)
What is the horizontal plane extending from maxilla?
Palatine process of maxillary bone
Has a suture- horizontal plate of palatine bone
What structure is a part of the soft palate and what does it consist of?
Uvula
Made of muscle -> Musculus uvulae
Red mucus membrane around it- covering whole of oral cavity and pharynx
What structure is exposed on protraction of the tongue?
Palatoglossal fold- under it is palatoglossal muscle
What structure is posterior to the palatoglossal fold?
Palatopharyngeal fold
Under it is palatopharyngeas muscle
What structure is between the palatoglossal and palatopharyngeas folds?
Palatine tonsil
Tensor veli palatini muscle and levator veli palatini muscle
Tensor- tenses soft palate
Levator- elevates soft palate
What innervates the muscles of the soft palate? Are there any exceptions?
Vagus nerve EXCEPT tensor veli palatini (supplied by mandibular division of trigeminal nerve)
Identify vagus nerve
First identify nearby common carotid artery
Lateral to it is internal jugular vein
In between them is vagus nerve
What structure is this
Root of tongue
attached to hyoid bone and mandible
What structure is this
Dorsum of tongue
What two parts is the tongue divided into?
Anterior 2/3 (oral)
Posterior 1/3 (pharyngeal)
What structure is this
Thyroid cartilage
What structure is this
Thyroid glands
What is the V shaped structure on the dorsal surface of the tongue?
Terminal sulcus
defines boundary between oral and pharyngeal parts of tongue
Foramen cecum
Thyroid gland started embryological development at this point, then descends
a shallow depression in the posterior dorsal midline of the tongue that is the remnant of the more cranial part of the embryonic duct from which the thyroid gland developed.
What connects foramen cecum to thyroid gland in embryos?
Thyroid glossal duct- atrophies after birth but can remain open as a thyroid glossal cyst in children
Identify this nerve
Lingual branch of mandibular division of trigeminal nerve
What sits here?
Trigeminal ganglion
What nerve gives sensation to oral part of tongue
Lingual branch of mandibular division of trigeminal nerve
What nerve travels with lingual nerve to send sensations of taste to brain?
Chorda tympani- branch of facial nerve
What nerve supplies sensation of taste and general sensation to pharyngeal part of tongue
Glossopharyngeal nerve (cranial nerve 9)
What structure is this
Parotid gland
Posterior to masseter muscle
What two vessels run through surface of parotid gland?
External carotid and retromandibular vein
What is this vessel and what structure is it going into?
Parotid duct going into buccinator muscle
Once in the oral cavity what is opposite the parotid duct?
2nd molar tooth upper jaw
What structure is this
Submandibular gland
What structure opens up in the mouth lateral to the frenulum?
Submandibular duct
Identify the structure
Frenulum
Identify the structure
Sublingual salivary glands
What are the 3 salivary glands?
Parotid glands
Submandibular glands
Sublingual glands
Pharynx
Fibromuscular tube that runs behind and is continuous with the nasal cavity, oral cavity and larynx
Identify the structures- what 3 parts is the pharynx divided into?
What is this structure?
Choanae- opening of nasal cavity (posterior nasal aperture)