DENDROLOGY

Detailed explanation-1: -A blue-black color results if starch is present.

Detailed explanation-2: -Dilute iodine solution is used to test the presence of starch in solutions. 2-3 drops of iodine solution are added to the solution to be tested. A blue-black colour appears if starch is present. In the absence of starch, the solution exhibits the golden yellow colour of iodine solution.

Detailed explanation-3: -The presence of starch in leaves can be tested by the Iodine test. When we remove chlorophyll from the leaf by boiling it in alcohol and then putting two drops of iodine solution, it is a colour change to blue indicates the presence of starch.

Detailed explanation-4: -The part of leaf that contains starch will turn blue black. The iodine reacts with the starch to give blue black color which is indicative of formation of starch-iodine complex. The leaves are the sources of starch due to process of photosynthesis.

Detailed explanation-5: -Using an iodine solution, you can test for the presence of starch. When starch is present, the iodine changes from brown to blue-black or purple.