When the plant is kept in sunlight the starch is formed in leaf.
Use iodine to test a leaf for starch | Plant Physiology | Biology
The function of starch in the leaf is to provide energy for the cell for the different functions. When the starch in the plant cells degrades, carbon is released so that it can be utilized in the production of sucrose.
then starch is not present...
Starch, I think, because iodine solution is the test for starch.
sucrose
because the leaves have photosynthesized- glucose is produced. therefore, the excess glucose is converted to starch. The starch is then stored in the leaf-starch is what causes the "green" leaf to turn blue black, as iodine turns blue-black when it reacts with starch.:P
Photosynthesis, the process by which glucose(and by proxy, starch) is produced requires chlorophyll, which gives leaves the green colour.
because photosynthesis has occured in the leaf. starch is produced and turns iodine blue-black indicating the presence of starch.
To determine the location of starch in a leaf, one can examine it under the microscope and apply one small drop of iodine to the leaf. The parts of the leaf that turn purple contain starch.
The leaf turns brittle during the testing the leaf for starch because the ethanol extracts the all water content from the leaf.
Starch is produced by leaves during Photosynthesis, therefore if the leaf has not been exposed to light then it will not contain starch, and so when tested the Iodine will stay Yellow/Brown. Consequently if the leaf has been left in the light Photosynthesis will have taken place and when tested the Iodine will go Blue/Black showing that Starch is present. Hope this helps :)
no
Use iodine to test a leaf for starch | Plant Physiology | Biology
A hot bath of ethanol decolorizes the leaf by washing out the chlorophyll. If the leaf is not decolorized, you cannot see the blue-black stain that results from the iodine reacting with the starch.
The starch in a variegated Coleus leaf is stored in the pigmented parts of the leaf. Coleus is a flowering plant is usually considered an ornamental plant because of its color.
It is to kill the cytoplasm, denaturate the enzyme and makes the leaf become more permeable to the iodine solution, therefor, we have to boil a leaf for starch test
The function of starch in the leaf is to provide energy for the cell for the different functions. When the starch in the plant cells degrades, carbon is released so that it can be utilized in the production of sucrose.