Upper and Lower GI Disorders - Introduction Flashcards
What are the mouth/throat functions (4)
- Taste
- chew and begin breakdown of food
- Regulate oesophagus/trachea
- speak
What is the anatomy of the mouth/throat (5)
- Salivation
- swallowing
- secreting digestive enzymes (amylase, lipase)
- secreting IgA and lysozyme (immune)
- avoids hepatic 1st pass
What are the functions of the tongue (3)
- Taste
- help chew (masticate)
- swallow
What is the function of the teeth
Cut, tear and chew food (mechanical break up for swallowing and digestion)
what is the function of the tonsils and adenoids
immune surveillance and response
What are the functions of the pharynx/larynx and epiglottitis (2)
- speak
- regulate oesophagus and trachea
What is the function of the oesophagus and upper stomach sphincter
Transport food and drink to stomach
What is the anatomy of the oesophagus (3)
- Long smooth muscular tube
- rhythmically pushes food bolus to stomach (peristalsis).
- Not designed for prolonged exposure to food/acid
What is the anatomy of the upper stomach sphincter
Strong muscular ring between oesophagus/stomach preventing acid reflux to oesophagus
What is the function of the stomach (3)
- Breakdown of food
- some absorption
- protect us by killing pathogens
What is the anatomy of the stomach (7)
- Large muscular sack can distend to hold around 1 L
- Sphincter at each end controlling movement (upper and pyloric sphincter)
- Secretes pepsin to break down food
- Parietal cells secrete H+ and Cl- ions to form hydrochloric acid
- Very acidic (HCl) to kill bacteria.
- Goblet cells secrete mucous lining to protect tissue from acid
- Some absorption
What are the functions of the small intestine (3)
- Digest food
- absorb nutrients & water
- excrete bile products
What is the anatomy of the small intestine (7)
- 6.5 meters long, highly vascularised
- Large surface area- Villi, microvilli
- Major site of digestion and nutrient absorption
- Duodenum - first 25 cm the entry point for chyme (gastric contents) and common bile duct.
- Secretes mucous and bicarbonate to neutralise chyme
- Jejunum - ~2.5 m long, absorption of sugars, amino acids and fatty acids
- Ileum - ~3 m long, absorbs Vitamin B12 and bile acids
What are the functions of the common bile duct (2)
- Transport bile and pancreatic secretions to small intestine to aid digestion and excretion.
- Enters via the ampulla of Vater
What is the anatomy of bile (3)
- Produced in liver and stored in gallbladder
- contains: bile salts, bilirubin, cholesterol and water.
- Emulsifies fats.
What is the anatomy of pancreatic secretions (2)
- Pancreatic lipase (needed for fat soluble vitamins A,Dand,E K),
- protease and amylase
What is the function of the large intestine (3)
- Absorb salts and water
- excretion
- form faeces
What is the anatomy of the large intestine (4)
- Wider than small intestine (diameter between 4-9 cm)
- 1.5 m long
- Highly vascularised tube
- Ending at colon
What are the functions of the rectum and anus (2)
- Temporarily store faeces
- control defecation
What is the anatomy of the rectum (4)
- Connected to but distinct from colon
- Around 12 cm long
- Stores faeces
- Blood supply goes directly into circulation (avoids hepatic 1st pass)
What is the anatomy of the anus (2)
- Muscular sphincter
- Controls voluntary defecation
