"What happens to the food we eat?"

http://www.bodecology.com/index.php/bod-e-411/300-day-04-tummy

No matter what we eat, we are eating proteins, carbohydrates and fats. In order to convert these three basic food materials into substances we can use, we need three groups of enzymes to aid in digestion: the protein-digesting enzymes (protease), the fat-decomposing enzymes (lipases) and the carbohydrate-decomposing enzymes (amylases) (“Digestion,” 2002). The main structures of the digestive system contained pharynx (throat), the oral cavity (mouth), stomach, large intestine (the cecum, appendix, colon, and rectum), small intestine (consisting of the duodenum, jejunum, and helium), esophagus, rectum and anus (Sizer, 2014). When food is digested, nutrients and water are taken in by the inside walls of some parts of the digestive system, while those that cannot be taken in leaves the body as waste. 

In the mouth, food is mixed with the saliva and transported through the esophagus into the stomach. The stomach sends signals, by means of hormones, to the gallbladder and the pancreas, to make sufficient enzymes available to digest the food in the intestinal tract (“Digestion,” 2002). The amylases in the stomach start by digesting the carbohydrates, initiated by the saliva in the mouth. To decompose the proteins in the food paste, the stomach produces one to two liters of gastric juice every day, containing hydrochloric acid and several protein-degrading enzymes, pepsin and cathepsin (“Digestion,” 2002). Finger-like projections called villi in the walls of the small intestine, which consists of arteries and veins, absorb the nutrients and transfer it to the blood vessels, which are followed by carried to the different cells in the body (Sizer, 2014). The waste products are transferred to the large intestine until disposal. 

For fun, I watched this episode of Magic School Bus about digestion. We got to learn together and spend time together. Enjoy! 

References

"Digestion." Science of Everyday Things. 2002. Retrieved September 12, 2016 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3408600125.html

Magic School Bus: For Lunch [Video file]. (n.d.). Retrieved from https://www.youtube.com/watch?v=IGk10GCW7r4

Sizer, F. & Whitney, E. (2014). Nutrition: Concepts and controversies (13th ed.). Mason, OH: Cengage Learning. ISBN: 9781133603184