A simple activity to make science learning interesting and easy was performed by the students in their practical class today.
When iodine solution is mixed with starch, it turns from brown to dark blue or blue-black. This is a simple test to show whether food contains starch.
Thin walled cells of many fruits, seeds and tubers are filled with colourless, membrane- bound organelles called ‘amyloplasts’. These plastids store starch grains and are localized in the storage organs. They may be small or large in size and variously shaped – oval, spherical or elongated.
The students performed the practical to test the presence of starch in various food stuffs using foldscope. To study where exactly the starch is located in a plant, various seeds were soaked in water for a few hours to make them soft. Thin sections were sliced and treated with Iodine solution. Examining the sections using a foldscope, the students could locate the position of starch as the grains turned blue-black.