Question

If the reaction worked and produced a positive result you would see

		your glass clearing due to the iodine hydrolyzing any starch that is present
		your glass turning a reddish brown due to the iodine reacting with any newly formed glucose
		your glass turning blue / black as your saliva causes the formation of glucose
		your glass clearing as your saliva hydrolyzes the starch into simple sugars

Answer 1

Answer-

According to the given question-

Starch hydrolysis test- is used for identification of bacteria capable of hydrolysing starch which have amylose and amylopectin with the help of a- amylase and oligo 1, 6 glucosidase.

Some bacteria use starch as carbon source and hydrolyze into small unit of sugar which join glycolysis pathway. Iodine form dark brown colour after reacting with starch present in the media.

Those bacteria which can hydrolyze the starch form clear zone observed around the growth of bacteria because these bacteria utilizes the starch as carbon source. While those are incapable of hydrolysing starch form dark blue colour with iodine.

Saluve contains amylase or ptylin enzyme which break starch into simple sugar.

So bacteria which form clear zone around their growth gives positive results for starch hydrolysis.

So correct answer is (D) your glass clearing as your saliva hydrolyzes the starch into simple sugars.