Enzymes in digestion Flashcards
What is the meaning of substrate specific?
Different enzymes digest and breakdown the different biological molecules contained in food.
Digestive enzymes are…..
Extracellular enzymes, they work outside of cells.
Three main types of digestive enzymes:
Carbohydrase’s, Proteases, and Lipases
What happens during the digestion of carbohydrates?
Amylase is a carbohydrase that hydrolyses (breaks down) starch into maltose.
Maltose is then hydrolysed into glucose by the enzyme maltase.
Where is Amylase made?
The salivary glands, the pancreas, and the small intestine.
Where is maltase found?
Found in cell-surface membranes of the epithelial cells lining the small intestine.
Why is there microvilli present in the small intestine?
Increases the surface area substantially allowing more membrane-bound disaccharases to fit and more absorption to take place.
Other disaccharidases in the cell-surface membrane of the epithelial cells in the small intestine:
Sucrase and Lactase
Why are there disaccharidases in the cell-surface membrane of the epithelial cells in the small intestine?
They allow the absorption of monosaccharides into epithelial cells of the small intestine which pass them into the blood stream.
Explain the process of emulsification
When the fatty liquid arrives in the small intestine, bile (containing bile salts) which has been made in the liver and stored in the gallbladder is secreted.
The bile salts bind to the fatty liquid and breaks the fatty droplets into smaller ones via emulsification.
Why is emulsification important?
Helps to increase the surface area of the fatty droplets for action of digestive enzymes.
Where does the digestion of lipids take place?
The lumen of the small intestine
Explain the digestion of lipids
Lipase enzymes break down lipids (fats) to glycerol and fatty acids.
Facts about Amylase
Substrate - carbohydrates
Produced in - Salivary glands + Pancreas
Released in - Mouth + small intestine
Facts about Maltase
Substrate - disaccharide
Produced in - small intestine
Released in - small intestine
