In the amylase activity experiment, the development of a blue-black color upon the addition of iodine-potassium-iodide to the test tube indicates that

A) the starch has been broken down.
B) the starch has been denatured.
C) amylase is functioning at its optimum temperature.
D) the starch has not been broken down.
E) glucose is present in the test tube.

Iodine-Potassium-Iodide

An aqueous solution made of iodine and potassium iodide used as a chemical indicator and antiseptic.

Amylase Activity

The process by which the enzyme amylase breaks down starches into simpler sugars, a key step in carbohydrate digestion.

Starch

is a carbohydrate consisting of a large number of glucose units joined together, serving as a key energy source in many plants and diets.