2.7 Factors Affecting Enzyme Action Flashcards
What two things does an enzyme need to work?
It needs to come into physical with its substrate, and it needs to have an active site which fits the substrate.
What two events are most frequently measured in an enzyme-catalysed reaction?
The formation of the products of the reaction, and the disappearance of the substrate.
What’s an example of the formation of the products of the reaction?
The volume of oxygen produced when catalase acts on hydrogen peroxide.
What’s an example of the disappearance of the substrate?
The reduction in concentration of starch when it is acted upon by amylase.
What type of energy does temperature increase?
Kinetic energy of molecules.
What can the temperature increase of a reaction also cause?
The hydrogen bonds in the enzyme to break, resulting in the enzyme changing shape.
What happens to a human enzyme at around 60ºC?
It denatures.
What is denaturation?
A permanent change the prevents the enzyme from ever functioning again.
What is the optimum temperature for most human enzymes?
40ºC
Why is our body temperature at 37ºC, which is lower than the optimum temperature for enzymes?
It would require additional energy, other proteins that aren’t enzymes may be denatured, and if we are ill, any further increase may denature them.
What is pH?
A measure of its hydrogen ion concentration.
What two ways can pH affect an enzyme’s effectiveness?
It can alter the charge on the amino acid that makes up the active site.
It can cause the bonds that maintain the enzyme’s tertiary structure to break.
