Question

1. which of the following is an example of a chemical change during digestion? *

a. muscles in the esophagus move food towards the stomach.
b. protein is broken down into amino acids in the stomach
c. water is absorbed into the bloodstream in the large intestine
d. teeth tear and grind food in the mouth into smaller pieces

Explanation:

A chemical change involves the formation of new substances. In option B, protein (a complex substance) is broken down into amino acids (new substances). In option A, it's just a physical movement. In option C, it's absorption (no new substance formed). In option D, it's a physical grinding (no new substance formed).

Answer:

B. Protein is broken down into amino acids in the stomach