Enzymes - effect of temperature on enzyme action Flashcards
1
Q
Give 3 factors that must be kept constant when investigating the effect of temperature:
A
- pH
- substrate concentration
- enzymes concentration
2
Q
What happens to the enzyme rate of reactions at a low temperature?
A
- low temperature is the limiting factor
- less energy
- low number of successful collisions —> low number of ESC formed —> low RoR
- Enzymes INACTIVE
3
Q
What happens when temperature increases?
A
- molecules (enzymes and substrates) gain kinetic energy
- more collisions
- more successful collisionsbetween active site and substrate
- more ESC formed
- RoR increases
4
Q
What happens when the temperature surpasses the optimum temperature?
A
- RoR decreases rapidly as enzymes DENATURE
- distortion of the active site
- active site is no longer complementary to substrate
- no ESC can form
- so RoR falls to 0
5
Q
Give 3 factors that must be kept constant when investigating the effect of temperature:
A
- temperature
- substrate concentration
- enzyme concentration
6
Q
Why does the rate of reaction decrease after the pH surpasses the optimum pH?
A
- pH becomes more acidic / alkaline than optimum pH —> enzyme DENATURES
- because active site changes shape —> no longer complementary to the substrate shape
- prevents ESC forming
- RoR decreases
7
Q
Explain a reason for the difference between the rate of rate for enzymes at difference pH’s ?
A
- different enzymes have different optimum pH levels
- Enzymes made by the stomach e.g. pepsin has acidic optimum pH ~2
- majority of human enzymes: optimum pH7
- trypsin: optimum pH ~9
