Alimentary Canal Flashcards
Where does digestion of carbohydrates begin ?
In the mouth
Where does digestion of proteins occur ?
In the stomach
Which organ makes digestive enzymes ?
Pancreas
What is the role of bile salts ?
Digestion and absorption of lipids
What is the role of the small intestine (2) ?
Chemical digestion and nutrient absorption
What is the role of the stomach (3) ?
- Storage
- Chemical digestion
- Sterilisation
What 3 roles does the large intestine have ?
- Water absorption
- Formation of faeces
- Bacterial fermentation
What is the mucosa made up of ?
The epithelium, lamina propria and the muscular mucosae.
Where are glands in the submucosa found ?
Duodenum and oesophagus.
Which two plexuses make up the enteric NS ?
Myenteric and submucosal plexuses.
What type of epithelium and the mouth and anus made of ?
Stratified squamous epithelium
What is found in the lamina propria ?
Blood vessels and glands
What is found in the submucosa ?
Blood vessels, glands, lymphatics and nerves.
What type of plexuses are the submucosal and myenteric ?
Parasympathetic plexuses
Which nerves control salivation ?
Facial and glossopharyngeal
What is sympathetic innervation via ?
Splanchnic nerves
What vein does the stomach blood drain into ?
Gastric vein
What vein does blood from the pancreas drain into ?
Splenic vein
Which veins does blood from the liver drain into ?
Hepatic veins
Is the hepatic portal circulation in parallel or in series with the gut circulation ?
In series
What type of sugars are monosaccharides ?
Hexose sugars
Give 3 examples of monosaccharides ?
Glucose, Fructose and Galactose
What is the name of the bond that holds two monosaccharides together ?
A glycosidic bond
Which enzymes break down glycosidic bonds between disaccharides and where are they found?
Brush border enzymes in the small intestine
What is Lactose broken down into ?
Glucose and Galactose
What is Sucrose broken down into ?
Fructose and Glucose
What is Maltose broken down into ?
Glucose and Glucose
What is starch made up of ?
A-Amylase and Amylopectin
Does A-Amylase have a straight or branched structure ?
Straight
Does Amylopectin have a straight or branched structure ?
Branched
In starch what are the bond between the monosaccharides ?
A 1-4 glycosidic bonds
What are A 1-4 glycosidic bonds broken down by ?
Amylases
Where are amylases produced ?
By salivary glands and the pancreas
What is the structure of cellulose ?
Unbranched straight chains of glucose linked by B 1-4 glycosidic bonds.
Can humans break down cellulose ?
No because they cannot make cellulase
How are glucose monomers linked in glycogen ?
By A 1-4 glycosidic bonds
What is the name of the membrane that faces the lumen ?
Apical membrane
What is the name of the membrane on the opposite site of the cell to the apical membrane ?
The Basolateral membrane
What type of junctions are found between the cells ?
Tight junctions
Define transcellular transport
Transport through the cells
Define paracellular transport
Transport between cells through the tight junctions