Clinical Intro to GI Tract Flashcards
What does the GI tract do?
Takes in food
Digests to extract and absorb energy and nutrients
Expels remaining waste
What is formed at the end of mastication?
Bolus
What are the three main salivary glands involved with eating?
Parotid
Sublingual
Submandibular
What type of saliva is produced by the parotid?
Serous
What type of saliva is produced by the submandibular?
Mixed
What type of saliva is produced by the sublingual?
Mucous
Which salivary gland is most active during eating/chewing?
Parotid
What are the digestive functions of saliva?
Form bolus
Amylase and lipase
Taste
What are the protective functions of saliva?
Dilution
Buffering
Lubrication
Remineralisation
Antimicrobial/antifungal/healing
What are the three regions of the pharynx?
Nasopharynx
Oropharynx
Hypopharynx
What prevents aspiration when you swallow?
Epiglottis
How long is the oesophagus on average?
25cm
How is food moved along the oesophagus?
Peristalsis
What are the four layers of the oesophagus?
Mucosa
Submucosa
Muscle layer
Adventitia
Describe the muscle arrangement of the oesophagus.
Upper third - voluntary
Middle third - mixed
Lower third - smooth
Describe the epithelium of the oesophagus.
Non-keratinised, stratified, squamous epithelium
At what level does the oesophagus pass through the diaphragm?
T10
At what level does the inferior vena cava pass through the diaphragm?
T8
At what level does the aorta pass through the diaphragm?
T12
What increases the secretion of saliva?
Parasympathetic and sympathetic stimulation
What decreases the secretion of saliva?
Sleep
Dehydration
Atropine
What are the characteristics of saliva?
Hypotonic
High HCO3- and K+
Contains α-amylase and lingual lipase
What increases the secretion of gastric acid?
Gastrin
Acetylcholine
Histamine
What decreases the secretion of gastric acid?
Chyme in duodenum
Somatostatin
Atropine
Cimetidine
Omeprazole
What increases the secretion of bile?
Cholecystokinin
Parasympathetic stimulation
What decreases the secretion of bile?
Ileal resection
What are the characteristic substances found in bile?
Bile salts
Bilirubin
Phospholipids
Cholesterol