The process of digestion occurs in consecutive stages, with one blending into the other. The tract is a special system concerned with the transport and assimilation of foods and fluids, and the rejection of undigested particles, plus other wastes from the body.
INGESTION: food is taken into the digestive canal through the mouth, pharynx, and esophagus.
SECRETION: enzymes, acids, and other chemicals are secreted for the breakdown of food. This starts in the mouth and continues into the small intestine.
ABSORPTION: water and the products absorbed through digestion are absorbed in the small intestine (mainly) and the large intestine (mostly water).
ASSIMILATION: food that has been absorbed is transported through the bloodstream and utilized by the cells of the body.
REJECTION: undigested particles, toxins, and poisons are expelled from the body
AFTER SWALLOWING: food takes 3 seconds to travel from the mouth to the stomach - it takes 5 minutes for the first mouthful to enter the duodenum and 20 minutes for half the consumed food to leave the stomach. in 4 1/2 hours the first mouthful has reached the start of the large intestine, the caecum. the first mouthful of food takes 9 1/2 hours to reach the end of the large intestine, the sigmoid colon. From start to finish, the complete process of digestions takes from 12 to 24 hours!