Anatomy of the Upper GI system Flashcards
What is the Gi tract lined with?
Mucosa (epithelium and lamina propria)
And muscle in the wall
What are the functions of the pharynx?
Swallowing
Defence again infection
Airway protection
What is the main function of the small intestine?
Digestion and absorption
Defence against infection (acid)
What is the main function of the large intestine?
Reabsorption of H20 and electrolytes
What is the name of the junction which splits the large and small intestine?
Ileocecal junction
What are the 3 muscles that close the jaw?
Temporalis
Massater
Medial pterygoid
What is the muscle that opens the jaw?
Lateral pterygoid
How do we prevent drooling?
Orbicularis Oris
- circular muscle around the lips, prevents dribbling during chewing and swallowing
Where do the muscles of facial expression lie?
Between the superficial fascia and fascial skeleton
What is the oral cavity lined with?
Mucosa - stratified squamous epithelium (for protection)
Where is keratin present in the oral cavity?
Only on the gingivae and hard palate
What is ‘special’ sensation linked with?
Taste
What is the dorsal surface of the Tongue?
The posterior side, the ‘top of the tongue
What are the 4 type of papillae on the tongue from anterior to posterior?
Filiform papillae (touch temp) Fungiform papillae (with taste buds) Foliate papillae and vallate papillae (singular)
Where are the extrinsic muscles of the tongue?
There are 4 paris
They attach the tongue to a bony skeleton
Moved the tongue around during mastication, speech and swallowing
Describe the intrisinc muscles of the tongue?
There are 4 paris in various direction, usually within the tongue
They change the shape of the tongue during function
Name the muscle of the cheek?
Buccinator
What does the buccinator do?
Aids in the manipulation of for to position it between the occlusal (biting) surface of the teeth
How many teeth does an adult have?
32
How is the teeth split up in the mouth?
4 quadrants
Upper right, upper left, lower right, lower left
What is an occlusion?
the way the upper and lower dental arches fit together (the bite)
What must you ask a patient with a suspected fracture of the mandible or maxilla?
How does your bite feel?
What does saliva contain?
Contains a lubricant (mucin) to aid swelling and speech and for keeping the mucosa moist
It is a buffer for plaque acids
What are the major salivary glands and describe their rough location?
Parotid (near ear)
Submandibular (under mandible)
Sub lingual (under tongue)
What stimulates saliva?
Thought sight, smell of food
Painful oral conditions - teething, fractured mandible
Describe the location of the ducts of the salivary glands?
Parotid - duct crosses face secretes into mouth by upper 2nd molar
Submandibular - duct enters floor of the mouth and secretes via lingual caruncle
Sublingual - lays in the floor of the mouth and secrets via several ducts superiorly
What is the pharynx lined with?
non-keratinised stratified squamous epithelium
Name the 3 different parts of the pharynx from superior to inferior?
Nasopharynx - posteror to nasal cavity superior to soft palate
Oropharynx - posterior to oral cavity between soft palate and epiglottis
Laryngopharynx- posterior to larynx between epiglottis and oesophagus
What is waldeyers tonsillar ring?
Provides defence again invading pathogens
Within the mucosa of the nasopharynx and oropharynx
Produces white blood cells
adenoid
tubal tonsil x 2
palatine tonsil x 2
lingual tonsil
What are the muscles of the pharynx, outer layer?
Circular muscles
3 x constrictor muscles
Push the food bolus down the oesophagus during contraction
Skeletal
What are the muscles of the pharynx, inner layer?
Longitudinal muscles
3 x paired vertical muscles
One contraction they pull the larynx superior shortening the pharynx during swallowing
What is the opening into the airway called?
The laryngeal inlet
What is the transition of muscle type in the oesophagus?
Skeletal muscle to smooth muscle
What is the oesophagus lined with?
Non-keratinised stratified squamous epithelium
Describe swallowing - the 2 steps including the pharynx?
Longitudinal muscles shorten pharynx and draws the larynx superiorly towards the epiglottis, closing the laryngeal inlet
Constrictor muscles sequentially contract pushing the food bolus towards the oesophagus,
