- How does the food change in consistency and form?
- As food enters the mouth, chewing breaks it down into smaller particles. Saliva starts breaking down carbohydrates which then allows the tongue to shape the mixture into a bolus, facilitating swallowing. In the stomach, acid and digestive enzymes further break down food to make chyme. In the small intestine, nutrients are absorbed, and in the large intestine or colon, water is absorbed, solidifying waste into feces for elimination.
- How could the body absorb the nutrients from the foods we eat?
- During carbohydrate digestion, it is broken down into glucose by enzymes and absorbed through the small intestine into the bloodstream.
- During protein digestion, enzymes break down proteins into amino acids. These amino acids are then absorbed in the small intestine through the intestinal lining and transported to various cells and tissues through our bloodstream. Our body then utilizes these amino acids for various functions, such as building and repairing tissues, producing enzymes and hormones, and supporting overall growth and maintenance (homeostasis).
- During fat absorption, it is emulsified by bile digested by lipase into fatty acids, and then absorbed by the body.
- Fat-soluble vitamins are absorbed with fats, and water-soluble vitamins are absorbed directly through the bloodstream.
- Minerals are absorbed in the small intestine through specific transport mechanisms and transported to tissues or stored.
REFERENCES:
Tortora, G. J., & Derrickson, B. H. (2017). Tortora’s Principles of Anatomy & Physiology. Wiley.
Dix, M. (2023, June 20). How is protein digested? Healthline. https://www.healthline.com/health/protein-digestion
khanacademymedicine. (2014, May 15). Meet the gastrointestinal tract! | Gastrointestinal system physiology | NCLEX-RN | Khan Academy [Video]. YouTube. https://www.youtube.com/watch?v=Oh_Pt_UrtEE