The small intestine has special structures that make absorption fast and effective. These include villi (finger-like projections) and microvilli (even smaller hair-like structures on villi). Together, they form a brush border that increases the surface area many times.

Key Structures

• Villi: contain blood capillaries and lymph vessels (lacteals) to absorb nutrients.
• Microvilli: tiny extensions on villi cells - create a brush border for maximum absorption.
• Thin walls: allow nutrients to pass quickly into blood/lymph.