Enzyme concentration on rate of reaction Flashcards
1
Q
Independent variable.
A
concentration of enzyme solution
2
Q
dependent variable.
A
time taken for enzyme to break down substrate
3
Q
other variables
A
- temperature
- pH (use a buffer solution)
- volume of substarte
- volume of enzyme solution
- concentration of substrate
4
Q
equipment
A
- protease (an enzyme which helps digest food) eg, 1% trypsin solution
- casein solution
- beakers
- distiled water
- syringe
- stop clock
- large beaker
5
Q
Method
A
- make different concentrations of enzyme solution with distilled water
- ensure different syringes are used for different chemicals to prevent cross contamination
- place one test tube of 5cm3 casein solution into a water bath alongside a second test tube containing 2cm3 of 0.2% trypsin
- allow to acclimatise for 3 mins then add trypsin to casein and start stop clock
- time how long it takes casein solution to turn transparent by marking an X on the other side of the tube and judge when you can see it through the solution
- repeat twice
- repeat for each concentration
6
Q
Evaluation issues.
A
- maintaining constant tempearture
- accurately making up different concentrations
- identifying end points
- difficult to see cross through the solution
- trypsin solutions above 1% are irritants
7
Q
What range of concentrations of trypsin should you use?
A
0.2%, 0.4%, 0.6%, 0.8% and 0.1%
8
Q
How much trypsin solution should be used?
A
2cm3
9
Q
How much casein solution should be used?
A
5cm3
