MOUTH AND OESOPHAGUS Flashcards
How many salivary glands are there and what are they called?
- Parotid gland
- Submandibular gland
- Sublingual gland
What action does the tongue do?
Pushes bolus of food to back of the mouth and also has sensory receptors to detect food
What is mastication and it’s importance?
- Mastication is chewing food and breaking it down to increase it’s SA:V ratio
- The purpose of this is so that there is more area for enzymes to work on and for absorption to take place
What does saliva do to the bolus of food?
Saliva lubricates food before swallowing
What type of cells are found in the salivary glands and what do they produce?
- Acinar cells - produce proteins and enzymes
- Ductal cells - secrete water and electrolytes
What is the volume of saliva that is produced by the salivary glands in 24 hrs
1.5 L
What type of saliva does each gland produce?
- Parotid - water
- Submandibular - viscous
- Sublingual - viscous
Which type of cells produce mucous ?
Goblet cells
What 3 substances does saliva produce for its immune function?
- IgA - IgA antibodies bind to pathogenic antigens
- Lactoferrin - binds iron and is bactericidal
- Lysozyme - attacks bacterial cell wall = cell lysis
How is the secretion of acinar cells modified?
Modified by salivary duct cells which makes saliva hypotonic and alkaline
Why is it important that saliva is alkaline?
- It protects the teeth from bacterial acid
- Neutralises gastric acid that refluxes into the oesophagus
What is sjorgren’s syndrome
An autoimmune attack of salivary and tear glands which results in dry mouth and eyes. It is associated with rheumatoid arthritis and commonly affects women
What is another name for mumps?
- Parotitis
What is the parasympathetic innervation of the submandibular gland and what does stimulation lead to?
- Facial nerve CN VII
- Stimulation results in secretion
What is the parasympathetic innervation of the sublingual gland and what does stimulation lead to?
- Facial nerve - CN VII
- Stimulation results in secretion
What is the parasympathetic innervation of the parotid gland and what does stimulation lead to?
- Glossopharyngeal nerve CNXI
- Stimulation results in secretion
What is the sympathetic innervation of the salivary gland and what does stimulation lead to?
- Thoracic sympathetics in the superior cervical ganglion
- Stimulation results in vasoconstriction and thick mucous secretion
What are the 4 phases to swallowing?
- Oral preparatory phase
- Oral phase
- Pharyngeal phase
- Oesophageal phase
What happens in oral preparatory phase?
Food is masticated (chewed) to reduce it to a consistency that can be swallowed
What happens in the oral phase?
The tongue properly food posteriorly until the pharyngeal swallow is triggered
When does the pharyngeal swallow occur?
When food gets to the back of the mouth in the oral phase
What happens in the pharyngeal phase?
Once the pharyngeal swallow is triggered, the bolus is transported through the pharynx
What 3 things occur in the pharyngeal phase so that the bolus can be transported through the pharynx?
- Closure of the glottis via the the movement of the epiglottis
- Cessation of breathing
- Relaxation of the upper oesophageal sphincter
What happens in the oesophageal phase
The bolus moves via oesophageal peristalsis from the upper oesophageal sphincter through the oesophagus to the lower oesophageal sphincter
