Question

Write an activity to show the effect of saliva on starch.

Answer 1

Experiment:

1. Boiled potato is used here in mashed form and separated into three parts.
   
2. Separate them in test tube A, test tube B and test tube C.
   
3. In the test tube A, iodine is added.
   
4. In the test tube B, iodine is added and then saliva is introduced.
   
5. In test tube C, nothing is added and kept as the control set.
   

Observation:

1. ​The test tube A, the iodine solution changes the boiled potato to blue color.
   
2. In the test tube B, saliva is introduced and mixed with the sample after adding iodine.
   
3. As a result, the color change will be observed when starch will be broken down to simple sugars like maltose.
   
4. The blue color starts reducing in the test tube B as the saliva containing the salivary amylase starts acting on the starch.
   
5. Test tube C shows no color change.
   

Inference:

1. The change in the test tube containing saliva shows the effect of salivary enzymes like salivary amylase on the boiled starch present in potato. ​