Final answer:
To check for remnants of starch on a plate, perform a test using iodine solution. If the iodine forms a blue-black color, it indicates the presence of starch.
Step-by-step explanation:
To check for remnants of starch on a plate, you can perform a simple test using iodine solution. First, put a few drops of iodine solution on the plate. If there are remnants of starch present, the iodine will form a blue-black color.
This color change occurs because starch and iodine react to form a complex known as the amylose-iodine complex. The blue-black color is a characteristic reaction that indicates the presence of starch.