1. Digestion
What do we know now?
Enzyme action

2. Factors that affect Enzyme activity
1 minute to list any factor that you think could change how fast an enzyme can work (hint… think kinetic energy / acidity / amounts)

3. To find out how enzymes are affected by temperature
Investigation
To find out how enzymes are affected by temperature
What could we change?

4. How does temperature affect the action of Amylase on Starch?
What will we change?
What will we keep the same?
What will we measure?

5. To help make this more reliable we will:

6. We are investigating.. How enzymes are affected by temperature
Our question is..
How does temperature affect the action of amylase on starch?
Complete the planning sheet
(using all the ideas we have talked about)

7. Method Iodine into wells on tile 5ml starch in syringe Wash outside
Add 1ml amylase to syringe
Quickly add air bubble and mix
Start clock
Place in water bath
After 30 seconds - remove, blot dry, add 1 drop of mixture to iodine
Replace syringe in water bath. Repeat iodine test every minute
Record time taken for iodine to stay yellow – in minutes
Wash out syringe and repeat

9. Own Results My temperature was..
Repeat 1
Repeat 2
Repeat 3
Repeat 4
Time taken for iodine to stay YELLOW/MINS
Start temperature End temperature..
My average time was:______
Enter this on the spreadsheet

10. Results spreadsheet

11. Time / seconds for each repeat
Temperature
(°C)
Time / seconds for each repeat 1 2 3 4 5 6
Mean 20
195 30
125 40 26 50 70 60
150 80
Did not digest

12. Graph to show how temperature affects the action of
amylase on starch
Average time for starch to digest / seconds
Temperature / oC

13. Rules for drawing a good graph
Use a ruler and sharp pencil
Use a linear scale (even intervals between numbers)
X axis
Independent variable (the factor you change)
Y axis
Dependent variable (factor you measure)
Label axes and don’t forget to add /units
Sharp, neat cross for each point
Smooth continuous curve to join points
Add a title