Question
How do villi increase the surface area?
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Answer
The villi has a finger like structure and the microvilli acts as a hairlike on those fingers. Both of them expand to increase the surface area so more nutrients can be absorbed. They both are made up of a single layer of cells. the villi and the microvilli increase intestinal absorptive surface area approximately 30-fold and 600-fold, respectively, providing exceptionally efficient absorption of nutrients in the lumen. There are also enzymes (enterocyte digestive enzyme) on the surface for digestion.
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