The ________, which begins the mechanical and chemical breakdown of food, is shown at letter E on the figure of the digestive system.

Mechanical Breakdown

The failure of a machine or device due to the wear and tear of its components or improper use.

Chemical Breakdown

The method of breaking down a substance into its basic elements or simpler compounds by means of chemical reactions.

Digestive System

The system of organs responsible for the breakdown and absorption of food and nutrients in the body.