Final answer:
Actin bundles give shape and support to microvilli found in intestinal mucosal cells.
Step-by-step explanation:
Actin bundles give shape and support to microvilli found in intestinal mucosal cells. Microvilli are small cylindrical extensions of the plasma membrane of the mucosa's epithelial cells, supported by microfilaments. These microvilli greatly expand the surface area of the small intestine, enhancing absorption.