explain activity 6.1, 6.2 and 6.3
The first two activities are already well explained in the study material at the link
Refer to this link and get back to us for doubts.
In the third activity, I am just providing you the logical reasoning as the steps are already provided to you.
When we perform the iodine test for both the tubes, the test tube in which saliva is added, shows less colouration of starch (blue black colour) as compared to the second tube.
This is because saliva has digested some percentage of starch in the tube.