Final answer:
The absorptive cells of the small intestine contain microvilli, which increase surface area and aid in nutrient absorption.
Step-by-step explanation:
The absorptive cells of the small intestine contain microvilli, which are small projections that increase the surface area of the small intestine and aid in the absorption of food. These microvilli are lined with epithelial cells and are found on the apical surface of each villus, which are finger-like projections that increase the surface area of the intestine. The presence of circular folds, villi, and microvilli vastly enlarges the absorptive surface area of the small intestine, allowing for efficient nutrient absorption.