What is the process by which teeth mechanically break down larger pieces of food?

The process by which teeth mechanically break down larger pieces of food is known as mastication. This term refers specifically to the act of chewing, where the teeth grind and crush food into smaller pieces, making it easier to swallow and aiding in the digestive process.

Mastication plays a crucial role in digestion as it increases the surface area of the food, allowing digestive enzymes to act more efficiently once the food reaches the stomach. This mechanical breakdown is essential for the proper functioning of the digestive system, as smaller food particles are easier to digest and absorb.

Other processes mentioned in the options also play important roles in digestion. Peristalsis involves the wave-like muscle contractions that move food through the gastrointestinal tract, emulsification refers to the process of breaking down fats into smaller droplets to enhance digestion, and churning typically describes the mixing of food in the stomach. However, these processes do not specifically refer to the mechanical action of breaking down food that occurs during chewing.