The reaction that takes place when starch molecules are converted into reducing sugars is called hydrolysis.

Here's why:

* Starch is a complex carbohydrate made up of long chains of glucose molecules linked together.

* Reducing sugars are simple sugars that have a free aldehyde or ketone group, allowing them to reduce other compounds. Common examples include glucose, fructose, and lactose.

* Hydrolysis is a chemical reaction where water is added to break down a larger molecule. In this case, water molecules are added to the bonds between the glucose units in starch.

This process breaks the starch chains into smaller units, ultimately resulting in the formation of reducing sugars like glucose.

Here's a simplified equation:

(Starch) + Water → (Reducing Sugars)

This reaction is catalyzed by enzymes like amylase, which are present in saliva and the digestive system of animals.