Enzymes Flashcards
What are Enzymes
They are proteins Called 'Biological Catalysts Reduces energy required to start a reaction Speed up reactions in the body Essentail to sustain life
What factors can affect enzymes?
The rate of an enzymatic reaction is affected by several factors, including:
- pH
- Temperature
- Enzyme concentration
- Substrate concentration
- Inhibition
What are subtrates?
Built or broken down molecules by the enzymes.
How do enzymes works?
They either:
- Speed up the breakdown of one substrate into multiple products
OR
- Speeds up the process for turning multiple substrates into one product.
Where is the active site on enzymes located?
on the enzyme where the substrate binds
What happens if the active site changes?
The enzyme will no longer work.
What happens to enzymes at optimum levels, give an example.
The enzyme will work to its fullest capacity (at its optimum temperature and pH)
Optimum factors depend on the environment where the enzyme is required.
- Pepsin is found in the stomach of humans. Its optimum temperature is around 37℃ and its optimum pH is around 2.
- Taq Polymerase is found in bacteria in hot springs. Its optimum temperature is 72℃ and its optimum pH is around 7.
What is it called when an enzyme is permanently changed?
It is called DENATURED
What does a high temperature or altered pH do to the enzyme?
It can permanently change the active site, therefore the enzyme can no longer bind with the active site of the substrate.
Bonds break and the protein loses its functional shape
When there is low temperature for the enzyme what happens?
The enzyme will be inactive - it won’t work to its full capacity, but it can be changed back.
What would happen if there weren’t enzymes?
Reactions may not happen fast enough to sustain life.
The enzymes lower the activation energy of the reaction, this means that it allows the reaction to occur more quickly.
How does temperature change affect enzyme activity?
Increase in temp -=increase in activity
- Increase in activity = increase in collisions between substrate and enzyme = faster rate of reaction
Effects of pH
Enzymes have an optimum pH at which it works.
Most work perfectly at pH 7 (neutral)
Optimum pH of an enzyme relates to the environment in which it works
Examples:
- Pepsin in the stomach (pH 2).
- Catalase works in a neutral environment of cells in the liver (pH 7)
- Alkaline phosphatase in bone (pH 9.5)
Enzyme concentration
Only a very small number of enzyme molecules are usually involved in a reaction and these produce a given amount of product per unit of time.
If the amount of enzyme is increased, the amount of product made per unit time increases.
Enzyme molecules are not used up in a reaction and are available for reuse.
Substrate Concentration
Amount of substrate or enzyme present in a reaction mix can limit the amount of product produced.
