End Overview Of GI Flashcards
Which domestic species is most prone to peritonitis? Why?
Horses
Due to small greater omentum
What is mastication?
Chewing
What is digestion?
The chemical breakdown of food by enzymes
What is absorption?
The GI system uses selective absorption. What type of proteins are used to do this?
The movement of a molecule from one place to another.
Specific transporter proteins
What is excretion?
The expelling of waste matter that has entered the blood stream
What is egestion?
The expelling of a waste product that has never been absorbed in the blood stream
What is regurgitation?
The passage of a material from the stomach into the mouth (passive) by smooth muscle contraction
What is vomitting?
The active passage of material from the stomach into the mouth
What groups make up food?
Protein, hCHO, non hCHO, fat.
Why do we need food?
For energy and amino acids
Why do we need amino acids?
For proteins: hormones, enzymes etc.
Hydrolysable CHO can be referred to as what? What bonds does this contain?
Starch
Alpha glycosidic bonds
Non hydrolysable CHO can be referred to as what? What bonds make up this?
Fibre
Beta glycosidic bonds
What happens to excess protein in the diet?
It is used for gluconeogenesis
What happens to excess glucose in the diet?
It is stored primarily as glycogen, then as fat
What is amylose?
Coiled polysaccharide of a glucose. Broken down by hydrolysis with amylase.
Where is amylase found in herbivores and omnivores?
In saliva and in the stomach
Where is amylase found in carnivores
Stomach only. Little starch in diet, not needed in saliva.
What is the pH of the mouth, stomach and SI?
Just below neutral (slightly acidic)
2
Just above neutral (slightly alkaline)
Where is acid produced?
Stomach
Omasum in ruminants
What is the purpose of stomach acid?
Destroy pathogens
What protects the GI from stomach acid?
Diaphragm
Which glands in the duodenum secrete alkaline mucus to neutralise stomach acid?
Brunner’s glands
What is the name of blood in faeces that has been digested? (Black, tarry stools. Shows problem with upper GI tract, e.g. stomach ulcers)
Melena
What is the word for ‘vomitting blood’?
Haematemesis
What is the word when bright red blood is present in stools? (Shows problem in lower GI tract, blood not digested)
Haematochezia
What is the alkaline tide? Why does this happen?
An increase in blood pH after eating
Increase of HCL made by parietal cells
Parietal cells secrete HCO3- across their basolateral membrane into the blood
On average, what is the total volume of secretion for a human?
10-12 litres
Animals secrete much more liquid than they take in. How do they compensate for that
Lots of reabsorption in the gut
What is the breakdown of fibre by microbes called?
Fermentation
All species ferment, but to different degrees
Why is foregut fermentation more effective than hind gut fermentation?
Amylolytic fermentation is very slow
Foregut fermenters can digest the microbes used for fermentation
What is diarrhoea caused by?
An increased fluid uptake in the gut
E.g. cholera, water fails to be reabsorbed.
What can cause diarrhoea and why?
Rapid change of diet
Enterocytes can’t regulate digestive enzymes and transporter proteins
What is laminitis? What causes this?
Inflammation of the laminae
Too much intake of hCHO, leads to a hormone imbalance
How can laminitis be reduced?
Avoid spring grass, as this contains more hCHO than grass does in other seasons
