Alimentary Canal Flashcards
What is the function of the mouth?
Foodstuffs broke down by chewing (mastication): saliva is added as a lubricant
What is the function of the oesophagus?
Conduit between the mouth and the stomach
What is the function of the stomach?
Digestion of proteins; foodstuffs reduced to liquid from. Also plays a role in storage and sterilisation
What is the function of the pancreas?
Digestive enzymes for digestion (duh), helps with the absorption of fats, carbohydrates and proteins
What is the function of the liver?
Secretes bile salts to aid the absorption of fats in the ileum
What is the function of the gallbladder?
Stores and concentrates bile
What is the function of the small intestine?
Final stage of chemical digestion and nutrient absorption
What is the function of the large intestine?
Water absorption, bacterial fermentation and formation of faeces
Describe the length, diameter and organisation of the GI tract
Approx. 8m long, varying diameter and organisation of cells vary depending on function
Describe the difference in the microscopic composition of the GI tract?
Mouth, anal canal and oesophagus - stratified squamous epithelium
Stomach and intestines - simple columnar epithelium
What are the four layers common to the GI tracts length?
- Mucosa
- Submucosa
- Muscularis externa
- Serosa/Aventitia
What structures comprise the mucosa?
Epithelium, lamina propria and muscularis mucosae
What is the function of the mucosa?
- Synthesis and secretion of enzymes
- bAbsorbs products of digestion
What is the lamina propria?
Loose connective tissue containing glands and blood/lymph vessels
What is the muscularis externa?
A thin layer of muscle
What is the structure of the submucosa?
Thick irregular connective tissue
What is the function of the submucosa?
Supports the mucosa