Absorption and digestion

Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream. There are four steps in the digestion process: ingestion, the mechanical and chemical breakdown of food, nutrient absorption, and elimination of indigestible food. The mechanical breakdown of food occurs via muscular contractions called peristalsis and segmentation

Digestion is a process of breakdown of large insoluble substance into simple absorbable form