B1.4 Enzymes and Digestion Flashcards
Enzyme
Biological catalysts which speed up reactions without being used up
Enzymes and temperature
The enzyme rate increases as temperature increases up to an optimum, after which the enzyme becomes denatured
Low temperatures and enzymes
Reduced chances of successful collision between enzymes and their complementary substrates
Effect of enzyme concentration
As enzyme concentration increases so will the rate of reaction, until saturation is reached
Enzymes and pH
The reaction rate decreases as the pH moves away from the enzyme’s optimum pH
Optimum rate
An ideal pH or temperature value that results in maximum enzyme activity
Denature
When the active site irreversibly changes shape and can no longer bind to a substrate due to high temperature or unsuitable pH
Active site
The part of an enzyme where the substrate binds
Substrate
Reactant of an enzyme catalysed reaction
Product
A substance produced in a chemical reaction
Lock and key theory
When a substrate fits into its enzyme just like a key fits a lock
Amylase
A carbohydrase enzyme found in saliva and the small intestine that breaks the chemical bonds in starches
Protease
Enzyme found in the stomach and small intestine that breaks down proteins into amino acids
Lipase
Enzyme found in the small intestine that breaks down lipids into glycerol and fatty acids
Carbohydrases
Enzymes that speed up the breakdown of carbohydrates into simple sugars
