Anatomy
What is the joint classification of the TMJ?
Synovial atypical modified hinge joint
What muscle types makes up the 3 sections of the oesophagus?
Upper-skeletal muscle
Middle third - both skeletal and smooth muscle
Lower third - smooth.
What is the Z line?
This is a line of transition of tissue type. It is located above the LOS and is where there is a change of gastric mucosa to oesophageal mucosa. (Change of simple columnar to non-keratinised stratified squamous epithelium.
What is the epithelial type lining the esophagus?
Non-keratinised stratified squamous epithelium.
Which gland is surrounded by a thick capsule and contains its own plexus of the facial nerve?
Parotid gland
What are the 3 stages of swallowing called, and which are voluntary and which are involuntary?
1. oral phase (voluntary)
2. Pharyngeal phase (involuntary)
3. Oesophageal phase (involuntary)
What are any 2 functions of the soft palate?
any 2 of these 3
- Facilitates nasal vs oral respiration.
- Allows us to chew and breathe at the same time
- Prevents food/ drink in the oral cavity passing prematurely into the pharynx due to its role in swallowing.
What type of drugs can cause xerostomia?
Anticholinergics
What nerve provides innervation to the muscles of the TMJ?
CN V3, mandibular branch of the trigeminal nerve.
What does constriction of the inner circular smooth muscle result in during peristalsis in the oesophagus?
Increase in intraluminal pressure.
What do chief cells secrete and at what depth are they typically located in the stomach epithelium?
Secrete pepsinogen, and located at the base of glands, in the lower levels of the epithelium.
*DAILY DOUBLE!* What are the 5 risk factors for squamous cell carcinoma (SCC)?
5 's'
- Smoking
- Spirits (alcohol)
- Sunlight
- Sepsis (with EBV or HIV)
- Suppression of p53 gene (tumour suppressing gene)
What are the two arches called that are in front of and behind the palatine tonsils?
Palatoglossal arch (infront)
Palatopharyngeal (behind)
What is primary and secondary peristalsis and when would the body use either?
Primary peristalsis - occurs following the pharyngeal phase of swallowing and is generally enough to move food along the esophagus. It is initiated by stretch receptors in the wall of the esophagus that detect distention.
Secondary peristalsis - This usually occurs if there is a large bolus or food left over in the esophagus. This can occur in the absence of oral and pharyngeal phases of swallowing.
Which nerve is involved with the afferent limb of the gag reflex, and stimulation of which parts of the upper GIT result in this?
CN IX - glossopharyngeal nerve, and stimulation of the palate, tonsil, posterior 1/3 of tongue, and posterior pharyngeal wall.
What are the two components of pleomorphic adenoma? Explain what you would see histologically for each.
1. epithelial component
- Lots and lots of ducts.
2. Mesenchymal component
- Tissues of mesodermal origin, bone, cartilage, or mucoid substance.
What specific nerve gives taste for the anterior 2/3 of the tongue, and what is it a branch of?
The chorda tympani nerve provides taste sensation to the anterior 2/3 of the tongue and is a branch of the facial nerve.
What is oesophageal achalasia, and what causes this? What is the chronic manifestation?
esophageal achalasia - this is a motor disorder where the lower oesophageal sphincter fails to relax properly.
This results in dysphagia, regurgitation, and chest pain.
It is due to defective innervation of the smooth muscle layer of the oesophagus and LOS.
Chronic manifestation - enlargement of the oesophagus due to accumulation of material at the LOS, can result in ulceration and rupture.
What is the zone of Askanazy? And what are the components of the bottom layer?
In relation to a gastric ulcer, and the layers seen histologically.
- Superficial - cellular debris
- Fibrinoid necrosis
- Deep - Granulation tissue.
- Granulation tissue components - new blood vessels, collagen, and fibroblasts.
What are the two types of chronic gastritis? And what is the process of each?
Type A - Autoimmune, results in Autoantibodies which destroys parietal cells and results in Achlorhydria (low acid in the stomach). Also results in anemia due to decreased B12 absorption.
Type B - H. pylori - stimulates cells to secrete acid resulting in increased acid in the stomach.