Enzymes Flashcards
Organisation (12 cards)
What do living things have going on inside them all the time?
Thousands of different chemical reactions
These reactions need to be carefully controlled to get the right amounts of substances.
How can you usually make a reaction happen more quickly?
By raising the temperature
This speeds up both useful and unwanted reactions.
What is a catalyst?
A substance that increases the speed of a reaction, without being changed or used up in the reaction
Enzymes act as biological catalysts.
What are enzymes made up of?
Chains of amino acids
These chains are folded into unique shapes necessary for their function.
What do enzymes need to do their jobs?
Unique shapes
The shape allows them to catalyze specific reactions.
What is the active site of an enzyme?
A region with a unique shape that fits onto the substrate involved in a reaction
Enzymes are specific to one reaction.
What happens if the substrate doesn’t match the enzyme’s active site?
The reaction won’t be catalyzed
This specificity is crucial for enzyme function.
What does the ‘lock and key’ model of enzyme action imply?
The active site of an enzyme is specifically shaped to fit a substrate
However, the actual process involves some shape change, known as the ‘induced fit’ model.
What happens to an enzyme if the temperature gets too high?
Some bonds holding the enzyme together break, changing the shape of the active site
This process is called denaturation.
What is the optimum temperature for an enzyme?
The temperature at which the enzyme works best
All enzymes have a specific optimum temperature.
How does pH affect enzymes?
If it’s too high or too low, it interferes with the bonds holding the enzyme together
This can change the shape of the active site and denature the enzyme.
What is the optimum pH for most enzymes?
Often neutral pH 7, but not always
For example, papain works best at pH 2.
