The first part of the small intestine is called the duodenum, where most food is broken down by enzymes. Later, the small intestine absorbs useful compounds from the digested food, which is done using small villi or tiny microvilli  - hair-like structures in the walls of the intestine.
- "Small intestine: biology of the digestive system: Merck Manual Home Edition". merckmanuals.com. 2011. Archived from the original on 24 January 2011. Retrieved 9 March 2011.
- Maton, Anthea; et al. (1993). Human biology and health. Englewood Cliffs, New Jersey, USA: Prentice Hall. ISBN 0-13-981176-1.