Scanning electron micrograph (SEM) showing a cross-section through a single villus from the intestine of a mouse. The absorption of nutrients through the gut wall is greatly enhanced by the presence of numerous villi, tiny finger-like projections that maximize the surface area of intestine available for absorption. The villus is constructed around an outer ring of columnar cells interspersed with mucous-secreting goblet cells. The goblet cells are distinguished by the granular secretory droplets they contain. Large blood vessels and smaller capillaries make up the core. Mag., x1500 at 8x10 inches in size.