Question

List the chemical changes undergone by a molecule of starch from the time it is placed in the mouth to its ultimate use in providing energy

Answer 1

The starch entering your mouth is treated with amylase and amylopectinase to hydrolyse it from a polysaccharide to maltose, a disaccharide. 

It is then treated with maltase to convert it into two molecules of the monosaccharide (alpha) glucose. 

It is then absorbed in the small intestine, and is used by the bodies cells in respiration for energy

Answer 2

Carbohydrates digestion at first begin in the mouth. The Salivary gland secrets saliva which is used at first to digest starch which is known as carbohydrates. The food is finally chewed where the salivary glands also release the enzyme salivary amylase which helps the process of breaking down the polysaccharides present in the food. Then it is digested in the stomach.