Final answer:
Chemical digestion is the process where food molecules are chemically broken down into simpler nutrients, which can then be absorbed into the bloodstream, primarily occurring in the small intestine.
Step-by-step explanation:
The process of chemical digestion occurs when food molecules enter the cells and undergo chemical changes. This process involves the chemical breakdown of large, complex food molecules into smaller, simpler nutrient molecules that can be absorbed by the blood. It begins in the mouth where saliva starts breaking down food, continues in the stomach with stomach enzymes, and mainly occurs in the small intestine. Enzymes through hydrolysis break down macromolecules like carbohydrates into simple sugars, proteins into amino acids, lipids into fatty acids and glycerol, and nucleic acids into nitrogen bases and sugars, readying them for absorption.
Chemical digestion is the biochemical process in which macromolecules in food are changed into smaller molecules that can be absorbed into body fluids and transported to cells throughout the body. Carbohydrates must be broken down into simple sugars, proteins into amino acids, lipids into fatty acids and glycerol, and nucleic acids into nitrogen bases and sugars. Some chemical digestion takes place in the mouth and stomach, but most of it occurs in the first part of the small intestine (duodenum).