Question

A physical change occurs in the digestive system when...

A. Gastric juices in the stomach convert proteins into amino acids.
B. Saliva changes complex carbohydrates into simple sugars.
C. Teeth break down and grind food particles into smaller pieces.
D. Pancreatic enzymes change fats into fatty acids and glycerol.

Answer 1

In the digestive system, a physical change occurs when the teeth break down and grind food particles into smaller pieces. This helps increase the surface area of the food for easier digestion by enzymes.

Step-by-step explanation:

In the digestive system, a physical change occurs when the teeth break down and grind food particles into smaller pieces. This process is called mechanical digestion. It starts in the mouth and continues in the stomach, where the food is churned and mixed with gastric juices. The purpose of mechanical digestion is to increase the surface area of the food, making it easier for enzymes to break down the food into smaller molecules during chemical digestion.