Enzymes Flashcards
Define Enzyme
A biological catalyst (speeds up processes in living things)
An enzyme’s shape is … to that of its substrate.
complementary
To speed up reactions, enzymes are a good alternative to higher temperatures. Why is this?
Because higher temperatures would not only speed up the useful reactions but also the unwanted ones.
Where does a substrate join to an enzyme?
The active site
How many substrates do enzymes usually work with?
One
Enzymes have a high … for their substrate.
specificity
Explain what happens to an enzyme when it gets too hot
Some bonds holding the enzyme together break
Active site changes shape
No longer complimentary to that of it’s substrate
The enzyme becomes denatured.
What do we call the conditions at which enzymes work best?
Optimum
Which pH do lots of enzymes work best in?
pH 7
What is pepsin’s optimum pH? And how does this suit its location?
pH 2 because pepsin breaks down proteins in the stomach and the conditions in the stomach are very acidic.
What are the 3 main factors that affect enzyme activity?
Temperature
pH
Substrate Concentration
Name the model used to explain the complementary shapes of enzymes and their substrates
‘Lock and Key’ model
