Digestion And Absorption Flashcards
Wha does digestion use to hydrolyse large and insoluble macromolecules into small soluble molecules?
Enzymes as they are to large to be absorbed through the lining cells of the ileum
enzymes are specific, different enzymes are needed for different
food types
What is the importance of physical dignestion?
IT increases the surface area available for enzyme activity
What is the general term given to enzymes that hydrolyse carbohydrates?
Carbohydrase
1)What breaks starch(polysaccharide) into maltose(disscharride) and what breaks maltose(saccharide )into alpha glucose ?
2)What breaks sucrose into a glucose and a fructose ?
3)What breaks lactose into glucose and galactose ?
1)Amylase (made in salivary gland and pancrease), maltase
2)sucrase
3)lactase
Where are the enzymes made and released into to take action?
Made in pancreas and released into small intestine
Not part of scheme just for you to know!!!
+100 amino acid =protein
100-3 = polypeptide
Less than 3 = dipeptide
Dipetide -2 amino acids joined together
What is the role of bile salts in lipid digestion?
Where are bile salts produced and stored?
-Bile salt emulsify lipids into tiny droplets to increase surface area available to lipase
-part of micelles production
-neutralises stomach acid
Produced in liver
Stored in gall bladder
BILE SALTS DO NOT HYDROLYSE LIPIDS
In relation to ileum what does co-transport mean?
Uptake of biological molecules associated with uptake of ion
Lipids
What is a micelle?
A tiny round complex formed from bile salts,fatty acids and monoglycerides.
Why is visking tubing a good model for the ileum ?
It is partially permeable so it will allow small molecules to pass through it but not large ones.
Lipids
What is a monoglyceride ?
A molecule of glycerol attached to only ONE fatty acid chain
At which ph does enzyme in the ileum work best ?
Why are several enzymes usually required to break down a biological molecule into monomers?
7
Enzymes are substrate specific so an enzyme that hydrolysed starch into maltose will not be able to hydrolyse maltose into glucose
Proteins
What is the difference between the action of endopeptidase and exopeptidase and dipeptidase ?
Endopeptidase hydrolyse peptide bonds in the central part of the polypeptide
Exopeptidase- hydrolyse amino acids from the ends terminal of the the peptide
Dipeptidase - they are exopeptidases located on the epithelial cells of the ileum. They hydrolyse peptide bonds
between dipeptides to produce individual amino acids. So now these amino acids can be absorbed into the eptihelial cells and the bloodstream
-this is all to create more surface area for enzyme activity and make them more smaller/soluble
