Session 2 - Salivation + Swallowing Flashcards
Name some of the functions of saliva
- lubricate and wets food
- starts digestion of carbs
- protects the oral environment
Describe zerostomia
- insufficient saliva production
- still able to eat food if it is already moist
- teeth and mucosa degrade very quickly
Name some components of saliva
- Water
- Electrolytes (High potassium and calcium)
- Alkali (High bicarbonate conc)
- Mucus
- Enzymes
Name the three salivary glands
Parotid, Sub-lingual and Sub-mandibular
Which of three salivary glands produces the highest volume of saliva?
Sub-mandibular - around 70% of total volume
How do the glands make the solution hypotonic?
- Increase the amount of ions in the solution
- water follows by osmosis
- ions are then removed but gaps are too small for water to pass through to solution remains hypotonic
What are the osmotic and ionic differences of saliva when there is a high flow rate?
- Less hypotonic as there is less time to remove sodium
- More alkali as more bicarbonate is secreted
What effect does parasympathetic stimulation of the salivary glands cause?
- Increases production of primary secretion
- ## Also increases amount of bicarbonate in saliva
What are three phases of swallowing?
- Voluntary Phase
- Pharyngeal Phase
- Oesophageal Phase
Describe the voluntary phase of swallowing
The tongue moves bolus back onto the pharynx
Describe the pharyngeal phase of swallowing
Set of movement triggered by stimulation of pressure receptors
- Inhibition of breathing
- raising of larynx
- closure of epiglottis
- opening of upper oesophageal ‘sphincter’
Describe the oesophageal phase of swallowing
Wave of peristalsis sweeps down oesophagus propelling bolus to the stomach through the now opened lower oesophageal sphincter
What is Dysphagia?
Symptom of difficulty when swallowing
What is Odynophagia?
Symptom of pain whilst swallowing
Describe some causes of Dysphagia
- motility problems of the smooth muscle in oesophagus
- obstruction or compression of oesophagus by a tumour
