Answer:
c) peristaltic contractions in the stomach churn a food bolus into liquid chyme
Explanation:
Chemical digestion describes the breakdown of substances into smaller components by chemicals.
The stomach acid breaks down proteins into their subunits - amino acids. The saliva breaks down long molecules of carbohydrates to sugar monomers. The bile in the small intestine digests fat molecules into their components - glycerol and fatty acid chains.
Peristaltic contractions move and churn the food in the stomach to form liquid, but this process does not describe the chemical breakdown of substances.
