Biology

Salivary amylase and starch

Tube no 1 2 3 4 5 6 7 8
Additives Starch Starch Starch Amylase Starch Maltose Starch Starch
Amylase Amylase Amylase Deionised water Deionised water Deionised waterAmylase Amylase
pH 7.0 buffer pH 7.0
buffer pH 7.0 buffer pH 7.0 buffer pH 7.0 buffer pH 7.0 buffer pH 2.0 buffer pH 9.0 buffer
Incubation
conditions Boiled then
incubated
at 37°C Freezefirst, incubateat 37°C 37°C 37°C 37°C 37°C 37°C 37°C

IKI Test








Benedict’s Test






Questions

1) What can you conclude about temperature effects on amylaseactivity from the results observed for tubes #1, #2 and #3? (2 marks)














2) What was the purpose of tubes #4 and #5? (1 mark)







3) Salivary amylaseactivity is greatly reduced in the stomach. Why? (1 mark)










Complete the following table:
Pepsin

Tube no 1 2 3 4 5 6
Additives Pepsin Pepsin Pepsin Deionized waterPepsin Pepsin
BAPNA BAPNA Deionised water BAPNA BAPNA BAPNA
pH 2.0 buffer pH 2.0 buffer pH 2.0 buffer pH 2.0 buffer pH 7.0 buffer pH 9.0 buffer
Incubation
conditions Boiled then incubated at 37°C37°C 37°C 37°C 37°C 37°C


Optical density







Questions

4) Under what conditions did the maximum hydrolysis of BAPNA occur? (1 mark)






5) How does the opticaldensity reading relate to protein digestion? (1 mark)










6) Using the simulation, design an experiment that would allow you to test how the amount of BAPNA digestion varies withtime? What is your conclusion? (4 marks)




















Lipase (complete the following table)


Tube no 1 2 3 4 5 6
Additives Lipase Lipase Lipase De-ionisedwater Lipase Lipase
Vegetable oil Vegetable oil Deionised water Vegetable oil Vegetable oil Vegetable oil
Bile salt Deionised water Bile salts Bile salts Bile salts Bile salts
pH 7.0 buffer pH...