Q: Intestinal villi (singular: villus) are small, finger-like projections that extend into the lumen of the small intestine. Each villus is approximately 0.5 -- 1.6 mm in length (in humans), and has many microvilli projecting from the enterocytes of its epithelium which collectively form the striated or brush border. Each of these microvilli are much smaller than a single villus. The intestinal villi are much smaller than any of the circular folds in the intestine.\n\nAnswer this question based on the passage: where are villi found in the small intestine? Let's give stream of consciousness first:
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This is the relevant information: Intestinal villi (singular: villus) are small, finger-like projections that extend into the lumen of the small intestine. Therefore, the final answer is the lumen.
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