Enzymes speed up the biological reactions necessary for life. Each type is specifically shaped to carry out one reaction. Enzyme activity can be affected by temperature.
Which types of cells make enzymes?
Animal cells only
Animal and plant cells only
Animal, bacterial, fungal and plant cells
What effect do enzymes have on the rate of biological reactions?
Increase in the rate
No change in the rate
What happens to an enzyme after it has catalysed a biological reaction?
It cannot be used again
It can be used again
Its structure is permanently changed
What is the name of a substance on which an enzyme acts?
Which word describes the relationship between the shape of the active site of an enzyme and the shape of its specific substrate?
Why is an enzyme described as specific?
It can catalyse only one reaction
It can catalyse many different reactions
It can speed up the rate of all biological reactions
Of which type of substance are enzymes made?
What happens during an enzyme catalysed reaction?
An enzyme binds to the active site of its specific substrate and the reaction occurs
A specific substrate binds to the active site of an enzyme and the reaction occurs
The active site of a specific substrate binds to the active site of an enzyme and the reaction occurs
What happens to enzyme activity at very high temperatures?
It increases to a maximum value
It decreases to zero
It is unaffected by temperature changes
What term describes the temperature at which an enzyme is most active?