Week 1 - Basic Structures And Processes Flashcards
Name the structures of the alimentary canal in order
Mouth Oesophagus Stomach Duodenum (pancreas coming off duodenum) Jejunum Ileum Large intestine Anus
What is the function of saliva?
Starts digestion (amylase and lipase) Bacteriostatic (IgA) Protects teeth (calcium) Assists swallowing
Is the oesophagus under voluntary or involuntary control?
Upper end - voluntary
Lower end - involuntary
Hoe does the oesophagus transport food?
Rapid peristaltic movement
What are the wrinkles in the stomach wall called?
Rugae
What is receptive relaxation?
Wall of stomach relaxes so pressure doesn’t rise, we eat faster than we digest
What does the stomach secrete?
Acid and proteolytic enzymes to break down and disinfect
Mucous to protect epithelium
What does the liver secrete into duodenum?
Bile containing water, alkali and bile salts (to emulsify fat)
What is the function of the duodenum?
Draw in water
Neutralise acidic chyme
Secrete enzymes to complete digestion
By terminal ileum whats happened to the bowel contents?
Nutrients absorbed but water still has to be absorbed
List structures of large intestine from start to end
Cecum (appendix off cecum) Ascending colon Transverse colon Descending colon Sigmoid colon Rectum
What causes urge to defaecate?
Stretching wall of rectum
Describe the neural control of GI tract
Somatic - controls ingestion and secretion
Autonomic controls the rest
Describe the paracrine control of GI tract
Substances act locally
Histamine - controls production of acid in stomach
Vasoactive substances - affect blood flow to gut
Describe the endocrine control of GI tract
Controls
secretion of stomach acid
Alkali secretion from liver and pancreas
Enzyme secretion
