GI Flashcards
Define mastication
The process of chewing by movement of jaw and tongue
How many teeth are present in the grown adult?
32
What are the 4 types of teeth present in the mouth? From anterior to posterior
Incisor
Canine
Premolars
Molars
What number of tooth is where the parotid gland secretes through into the mouth
Upper tooth 7, molar 2
What are the four muscles of mastication?
Temporalis major
Masseter
Lateral ptyergoid
Medial ptyergoid
The TMJ has two cavities for specific movements, what are these?
Superior cavity for translation
Inferior cavity for rotation
What are the three divisions of the trigeminal nerve? CN V
V1 opthalmic
V2 maxillary
V3 mandibular
What is the attachment of CN V3 in the brain and the formamen it passes through to then supply what muscles?
Pons
Foramen ovale
Muscles of mastication
What are the four types of papillae on the tongue? Where are they located?
Vallate papillae (v shape) posterior part of tongue
Follate papillae (F far to the side)
Fungiform papillae ( middle of tongue)
Filiform (Fili like villi so touches food and senses temp, at tip of tongue)
What is the nerve supply to the tongue?
Posterior part CN IV (trochlear)
Anterior 2/3rd CN VII (facial
General sensation CN V3 (trigeminal mandibular)
Describe the course of the facial nerve from the brain to innervate the tongue
Attaches at the pontomedullary junction to then pass through the internal acoustic meatus then the sylomastoid foramen
It then bifurcates to become the chorda tympani and joins with CN V3 nerve to supply the submandibular salivary glands
Describe the innervation of the superior part of the oral cavity?
CN V2 trigeminal maxillary nerve
Describe the innervation of the inferior part of the oral cavity?
CN V3 trigeminal mandibular section
Spraying a local anesthetic in the mouth is to suppress the gag reflex for endoscope. What nerves does this block?
CN V2
CN V3
CN VII
CN IX
What is the course of the CN V2 nerve from the brain?
From pons
Through foramen rotundum
To sensory area (mid face)
Describe the course of the CN IX nerve (glossopharyngeal)
Medulla
Jugular foramen
Supplying posterior wall of oropharynx
Parotid gland and posterior 1/3 of tongue
What are the three salivary glands and where do they secrete via
Parotid 2nd molar
Sublingual through floor of the mouth
Submandibular through the lingual carnucle
What nerves innervate the salivary glands
Parotid by the trochlear (CNIX)
Sublingual by facial nerve (CNVII)
Submandibular by facial nerve (CNVII)
What are the four pairs of skeletal muscles of the tongue? Working clockwise from roof of mouth to front of mouth
Palatoglossus
Styloglossus
Hyoglosssus
Genioglossus
What are the skeletal muscles of the tongue innervated by ?
The hypoglossal nerve except from the palatoglossus
Describe the course of the hypoglossal nerve
From medulla
Through hypoglossal canal
To extrinsic and intrinsic muscles of tongue
What nerves innervate the posterior part of the pharynx
The vagus nerve mainly and one muscle supplied by the glossopharyngeal CNIX
What is the vertebral level of the upper oesophageal sphincter?
C6
The circular muscles of the pharynx all attach to what structure?
Midline raphe
Describe the structures involved in the process of swallowing
Lips close to prevent drooling, orbicularis oris
Tongue pushes food towards oropharynx
Soft palate elevates and the larynx elevates
Circular layers of pharyngeal muscles contract
Food enters oesophagus and travels inferior by peristalysis
What structures are included in the foregut?
Oesophagus Mid duodenum Liver Gall bladder Spleen 1/2 pancreas
What structures are involved in the midgut?
Mid duodenum
2/3 transverse colon
1/2 pancreas
What structures are involved in the hindgut?
Distal 1/3 of transverse colon Descending colon Sigmoid colon Rectum Anal canal Anus
What muscles can be involved in guarding ?
Rectus abdominus External oblique Internal oblique Transversus abdominus Parietal peritoneum
What can cause peritonitis?
Blood
Fluid
Pus
Faeces in the peritoneal cavity
What is an intraperitoneal organ?
One that is almost completely covered in visceral peritoneum so they are minimally mobile
What is an mesentery organ?
One that has a mesentery, where the visceral peritoneum wraps behind the organ to form a double layer, also known as intraperitoneal. Hence these are very mobile
What is a retroperitoneal organ?
One that only has visceral periotoneum on its anterior surface aka is behind the peritoneum
Give an example of an intraperitoneal organ
Transverse colon Liver and gall bladder Stomach Some small intestines Spleen
Give some examples of retroperitoneal organs
Kidneys Adrenal gland Pancreas Ascending colon Descending colon
What are the attachments of the greater omentum?
Attaches greater curvature of the stomach to the transverse colon