1.5 Enzymes Flashcards
What are enzymes?
Globular proteins that act as biological catalysts
What are competitive inhibitors?
Molecules that bind to the active site of an enzyme, preventing the substrate from binding
What is end-product inhibition?
A method of enzyme inhibition where the product of an enzyme controlled reaction can bind to the enzyme, preventing it from working
What is an enzyme-product complex?
The temporary complex formed after the enzyme has catalysed the reaction but before the products have left the active site of the enzyme
What is an enzyme substrate complex?
The temporary complex formed when the substrate binds to the active site of an enzyme
What is an extracellular reaction?
A reaction that occurs outside of cells
What is the induced-fit hypothesis?
A model of enzyme action that describes how once a specific substrate binds to the active site, the enzyme undergoes subtle conformational changes to fit the substrate better
What is an intracellular reaction?
A reaction that occurs inside of cells
What is the lock and key hypothesis?
A model of enzyme action that describes how the enzyme will only fit a substrate that has the correct complementary shape to the active site
What are non-competitive inhibitors?
Molecules that bind to a different part of an enzyme known as the allosteric site, preventing the enzyme from functioning
What two sites are on an enzyme?
The active site and the allosteric site
What is pH?
A measure of the acidity or alkalinity of a solution
What does the term rate of reaction mean?
The change in concentration of reactants or products over time
What is a substrate?
A molecule or molecules that bind to the active site of an enzyme and are acted upon by the enzyme
What is meant by the term substrate specificity?
The ability of an enzyme to catalyse only a specific reaction or set of reactions which have substrates complementary to the active site of the enzyme
