What do we call the process of breaking down food into smaller components?

The correct answer is digestion, which is the process through which food is broken down into smaller components that can be absorbed and utilized by the body. Digestion involves both mechanical and chemical processes; mechanical digestion includes chewing and the churning of food in the stomach, while chemical digestion involves enzymes and acids that break down food substances into nutrients such as carbohydrates, proteins, and fats.

In this context, ingestion refers specifically to the act of taking in food and liquids, rather than breaking them down. Respiration is the process by which organisms convert oxygen and glucose into energy, which is separate from the food breakdown process. Circulation concerns the movement of blood throughout the body, distributing nutrients and oxygen, but it does not involve the breakdown of food itself. Thus, digestion is the specific term that accurately describes the breakdown of food into smaller, absorbable parts.