Enzymes Flashcards
What are enzymes?
They are biological catalytsts, meaning they increase the rate of reactionby lowering the activation energy needed. They are a globular protein.
What is a substrate?
A molecule that binds to the active site of an enzyme, then taking part in it thus meaning its a reactant.
What are the two different models and what do they do?
Firstly there is a lock & key model this is when the enzyme shape is perfectly complementary to the substrate, the active site of the enzyme and specific substrate fit together like a “lock and key”. The second model is the induced fit, which means it is flexible and changes shape a little when the substrate binds to it, thus creating a tighter fit, this is a more accurate representation as the active site is somewhat flexible.
What are cofactors?
They are any molecule an enzyme needs to function efficiently, they are also know as enzyme activators.
What are coenzymes?
Coenzymes can bind to an inactive enzyme and make it become active, they also serve as carriers during aerobic respiration. Some examples are NADPH in photosynthesis as they act as carriers for hydrogen within photosynthesis.
How is temperature a factor for enzyme regulation?
This is because when the temperature is too low the molecules have less kenetic energy thus meaning theres less
What is a non-competitive inhibition and inhibitor?
A non-competitive inhibitor is when the inhibitor doesn’t bind to the active site but causes a change in the tertiary shape of the enzyme, thus blocking the enzyme from working because the substrate cant bind to it. The non-competitive inhibitor decreases the amount of product that can be made, it also cannot reach maximum reactionr ate evven with high substrate levels. Lowers the maximum rate reaction.
What are competitive inhibition and inhibitors?
Competitive inhibitor binds to the active site and competes with the substrate for binding to the enzyme, a competitive inhibition decreases the reaction rate by making it slower to convert substrate into product. Slows the time it takes to reach maximum rate of reaction.
