Final answer:
The breaking down of food into amino acids, fatty acids, and glucose for cell assimilation is known as digestion, a process where food is mechanically and chemically broken into smaller fragments for absorption.
Step-by-step explanation:
The breaking down of food into amino acids, fatty acids, and glucose that can be easily assimilated by the cells is known as digestion. This process involves the mechanical and chemical breakdown of food into smaller organic fragments that can be absorbed across the digestive epithelium. Proteins are digested into amino acids, fats into fatty acids, and carbohydrates into glucose molecules by various enzymes throughout the digestive system. The glucose can be used for immediate energy or stored as glycogen, the fatty acids can enter the Krebs cycle for energy production or stored as triglycerides, and amino acids can be used to synthesize new proteins or converted to glucose or ketones when in excess.