Cambridge O Level Biology · Syllabus 5090 · Human Nutrition
Villus
What is Villus?
A small finger-like projection of the wall of the small intestine, made of many cells, which increases the surface area available for absorption. Its epithelium is one cell thick, its exposed surface carries microvilli, and inside it are a dense network of blood capillaries and a central lacteal.
This definition is part of the Human Nutrition chapter in Cambridge O Level Biology.
Common mistakes with Villus
- “A villus is a cell.” Why it is wrong A villus is a projection of the intestinal wall made of many cells, containing a capillary network and a lacteal. A single cell contains neither. Write instead "A villus is a finger-like projection of the wall of the small intestine, covered by an epithelium one cell thick."
- “All the water is absorbed in the colon.” Why it is wrong Most water is absorbed in the small intestine, where the villus surface is enormous. The colon absorbs the remainder, which is why the visible change to firm faeces happens there. Write instead "Most water is absorbed in the small intestine; further water is absorbed in the colon."
Questions students ask about Villus
Is a villus a single cell?
No. A villus is a finger-like projection of the wall of the small intestine, made of many cells. Its outer covering, the epithelium, is one cell thick, and inside it are a dense network of blood capillaries and a central lacteal — none of which a single cell could contain.
Last reviewed Syllabus 2026-2028