Digestion, Absorption, and Metabolism Baby!

 Digestion is the process of food being broken down through the body through mechanical and chemical processes so the body can obtain the macro and micro-nutrients that it needs from substances it can use (Sizer & Whitney, 2014).  When macro-nutrients are digested, it begins in the mouth where enzymes are released to chemically break down food and the teeth mechanically break down food so it can be swallowed, in the stomach an enzyme called pepsin to digest proteins and carbohydrates are broken down into sugars that the body then absorbs and uses for energy (Food and Digestion, 2004). Carbohydrates, such as starches like bread, need amylase to digest within the chemical process, the proteins, such as nuts, need protease to digest within the chemical process, and fats, such as olive oil, need lipase to digest within the chemical process and this takes place in the food's next stop - the intestines where the body absorbs nutrients (Food and Digestion, 2004). The small intestine is responsible for secreting the enzymes and absorbing the nutrients into the blood and lymph and is made possible by the villi and micro-villi covering the inside of the intestine that create an extreme amount of surface area which allows for vast amounts of absorption (Food and Digestion, 2004), while the small intestine then reabsorbs water and minerals then passes the wastes such as fiber, bacteria, and unabsorbed nutrients to the rectum (Sizer & Whitney, 2014). After digestion and absorption, nutrients are then carried to the cells in the body and are changed into energy through the process of metabolism, this happens through either aerobic metabolism or anaerobic metabolism (Sizer & Whitney, 2014).

(Jenny4ever, Absorption)

References

Food and digestion. (2004). Retrieved June 16, 2014, from http://digital.films.com.proxy-library.ashford.edu/PortalPlaylists.aspx?aid=18596&xtid=35548  

Jenny4ever. (Producer). (2012, Dec 10). Absorption [Web Photo]. Retrieved from http://www.proprofs.com/flashcards/story.php?title=chapter-3-nutrition

Sizer, F., & Whitney, E. (2014). Nutrition - concepts and controversies. Belmont, CA: Cengage Learning.