| The job of the intestine is to absorb food. To provide maximum surface area, the absorptive surface of the intestine is shaped into billions of finger-like projections called villi. This is a cross-section of one villus. The absorptive epithelial cells are on the outside of the villus (green). The orange and yellow cells in the center include blood vessels, nerves, muscle and immune cells, all of which function with the epithelial cells as a cohesive unit designed for absorption. |