The highly folded mucous membrane lining the small intestine is magnified 650 times in this scanning electron micrograph. The folds are covered with a forest of narrow, finger-like projections called villi, which are specially adapted for absorbing digested food. The villi are crowded so close together that they make the mucous membrane look velvety at this scale. The fold and the villi combine to provide the gut with an enormous surface area of 250 square meters for digestion and absorption.