Grand Tour of Alimentary Canal Flashcards
Where are the salivary glands?
Parotid
Sublingual
Submandibular
What is the function of the mouth in digestion?
Chewing - breakdown
Saliva - lubricant, enzymes
What is the general function of the stomach?
Digestion of proteins
Storage
Sterilisation
Reduction to liquid form
General function of the pancreas?
Digestive enzymes for fats, carbs, proteins
General function of the liver for digestion?
Production of bile salts (absorption of fats)
General function of the gallbladder?
Storage and concentration of bile
General function of the small intestine
Final stage chemical digestion
Nutrient absorption
General function of the large intestine
Water absorption
Bacterial fermentation
Formation of faeces
What are the 4 layers(tunics) of the alimentary canal?
Mucosa Submucosa Muscularis externa Serosa (inside peritoneal cavity) Adventitia (outside peritoneal cavity)
Glands are displayed in the submucosa of which parts of the GIT?
Oesophagus
Duodenum
Orientation of muscularis externa
Two concentric rings, one contracting circularly, one contracting longitudinally
Which nerve plexuses lay in the GIT?
Myenteric plexus
Submucosal plexus
The mucosa of the GIT contains which layers?
Epithelium
Lamina propria
Muscularis mucosae
What form of epithelium lines the mouth, oesophagus and anal canal?
Stratified squamous (non-keratinizing)
What form of epithelium lines the stomach and intestines?
Simple columnar
What is the role of the lamina propria?
Loose connective tissue
glands, blood/lymph vessels
What is contained within the submucosa?
Neurones
Blood vessels
Lymphatics
What type of tissue is contained within the submuscosa?
Thick, irregular connective tissue
Submucosal glands are present in which sections of the GIT?
Oesophagus and Duodenum
How is the serosa differentiated from the adventitia?
Adventitia attaches oesophagus and rectum to surrounding structures
Serosa surrounds stomach and intestines
Describe the structure and function of muscularis externa?
Inner: Circular muscle (constriction)
Outer: Longitudinal muscle (shortening)
Both function for peristalsis and segmentation
What lies between the longitudinal and circular muscles?
Myenteric/Auerbach’s plexus
Long autonomic control of the alimentary system is supplied by what?
Parasympathetic system
Short autonomic control of the alimentary system is supplied by what?
Enteric Nervous system
What nerves provide parasympathetic supply of the Alimentary system?
Vagus nerve (X) Facial nerve (VII) Glossopharyngeal (IX)
Which nerve provides sympathetic innervation of the alimentary system?
Splanchnic nerve
What are the 3 main arteries of the GIT?
Coeliac trunk
Superior mesenteric artery
Inferior mesenteric artery
The celiac trunk supplies blood to what?
Stomach
Small intestine
Pancreas
Liver
The superior mesenteric artery supplies blood to what?
Small intestine
Caecum
Ascending colon
Transverse colon
The inferior mesenteric artery supplied blood to what?
Descending colon
Sigmoid colon
Rectum
What are the 4 main tributaries of the hepatic portal vein?
Gastric Veins
Splenic vein
Superior/inferior mesenteric vein
What makes a portal system?
A vascular system with capillary beds at both ends
