Enzymes Flashcards
What are enzymes?
Catalysts produced by living things
What happens in living things thousands of times?
Chemical reactions - they need to be carefully controlled to get the right amount of substances in a cell
What can you do normally to make a reaction happen more quickly?
Raise the temperature - however there is a limit to how high it can go as it can start to damage the cell
What do living things produce to help the temperature problem?
Biological catalysts
What is a catalyst?
A substance which increases the speed of the reaction without being changed or used in the reaction
What do enzymes speed up specifically?
Metabolic reactions
What are enzymes made out of?
Proteins which in turn are made up of amino acids which are folded into unique shapes, which enzymes need for their jobs
What do chemical reactions usually involve?
Things either being split apart or joined together
What is a substrate?
A molecule that is changed in a reaction
What does every enzyme molecule have?
An active site where the substrate joins ont the enzyme
Why are enzymes very specific?
They only speed up one reaction at a time and need the correct substrate to fit the active site otherwise it wont work
What can be used to demonstrate the substrate fitting onto the active site?
The “lock and key” model
What does changing the temperature do?
Change the rate of an enzyme-catalysed reaction
What happens at the beginning of a enzyme-catalysed reaction?
As the temperature increases, the rate increases - this is because the enzymes and substrate have more kinetic energy there is a high collision rate between the active site and substrate
What happens at low temperatures in an enzyme-catalyst reaction?
There is a lower collision rate between the substrate and active site so the rate of the reaction is slow
