AB2.H1.10 Area for Absorption
Area for Absorption:
- Absorbtion of nutrients and water is a main fimction of the small and large intestines
- This is facilitated by four structural adaptations of the gut tube
- Two of these are gross adaptations which can be seen with the naked eye
- Two are features which can only be visualised by microscopy
- The four structural adaptations of the intestine to facilitate absorbtion are:
- The long length of the intestine itself provides a large surface area across which absorbtion can take place
- In the small intestine, there are permanent folds in the submucosa - the plicae circulares - these greatly increase the surface area of the lumen
- The mucous membrane in the small intestine forms villi which project into the lumen of the gut tube
- The absorbtive cells have microvilli on their apical surface