DigestionWhat do we know

now?

Enzyme action

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)

Investigation

To find out how enzymes are affected by temperature

What could we change?

How does temperature affect the action of Amylase on Starch?

• What will we change?

• What will we keep the same?

• What will we measure?

To help make this more reliable we will:

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)

1. Iodine into wells on tile2. 5ml starch in syringe3. Wash outside4. Add 1ml amylase to syringe5. Quickly add air bubble and mix6. Start clock7. Place in water bath8. After 30 seconds - remove, blot dry, add 1 drop of

mixture to iodine9. Replace syringe in water bath. Repeat iodine test

every minute10. Record time taken for iodine to stay yellow – in

minutes11. Wash out syringe and repeat

Method

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

Results spreadsheet

Temperature(°C)

Time / seconds for each repeat

1 2 3 4 5 6 Mean

20 19530 125

40 2650 7060 15080

Did not digest

Temperature / oC

Avera

ge t

ime f

or

starc

h t

o d

igest

/

seco

nd

s

Graph to show how temperature affects the action of

amylase on starch

Rules for drawing a good graph

Use a ruler and sharp pencilUse a linear scale (even intervals between numbers)

X axisIndependent variable (the factor you change)Y axisDependent variable (factor you measure)

Label axes and don’t forget to add /unitsSharp, neat cross for each pointSmooth continuous curve to join pointsAdd a title