Digestion & Absorption Flashcards
Where is amylase produced and secreted?
- produced in salivary glands and pancreas
- pancreas secretes amylase into small intestine
What is the function of amylase?
To hydrolyse starch into maltose
What are membrane-bound disaccharides?
- enzymes that hydrolyse disaccharides to monosaccharides
- maltase, sucrase & lactase
Where are membrane-bound disaccharides found?
Present in the membrane of the small intestine
What is the function of lipase?
To hydrolyse lipids to monoglycerides + fatty acids
Where are lipases found?
In the small intestine
What are some adaptations in the break down of lipids?
- bile salts emulsify lipids so they have a larger surface area for hydrolysis
- products can remain associated with bile salts to form micelles
- micelles travel to the ileum + are broken down when in contact with epithelium so products diffuse straight into epithelium
What is the function of protease?
To hydrolyse proteins into amino acids
What are the 3 types of proteases?
Endopeptidases
Exopeptidases
Membrane-bound dipeptidases
What are some examples of endopeptidases?
Trypsin, chymotrypsin + pepsin
What do endopeptidases do?
Hydrolyse peptide bonds in the middle region of the polypeptide chain
What do exopeptidases do?
Hydrolyse emptied bonds on terminal amino acids
What do membrane-bound dipeptidases do?
Hydrolyse dipeptidases into 2 amino acids
What is the sodium-potassium pump
A protein pump that transports sodium ions out of the cell + potassium ions into the cell
What does the sodium-potassium pump maintain?
- higher concentration of Na ions outside the cell
- higher concentration of K ions inside the cell
- also helps stabilise cells membrane potential
