Here's the breakdown of the levels of structure leading to the villi, starting from the broadest level and going down to the specific structure:

1. Organism: The entire living being, in this case, a human or other animal with a digestive system.

2. Organ System: The digestive system, responsible for breaking down food and absorbing nutrients.

3. Organ: The small intestine, the primary site of nutrient absorption.

4. Tissue:

* Epithelial tissue: The lining of the small intestine, composed of specialized cells that absorb nutrients. This includes the absorptive cells that form the villi.

* Connective tissue: Forms the core of the villi, providing support and structure.

5. Villi: These are finger-like projections extending into the lumen (inside space) of the small intestine. They dramatically increase the surface area available for absorption.

6. Microvilli: Tiny finger-like projections on the surface of epithelial cells within the villi. They further increase the surface area for absorption, making it incredibly efficient.

In Summary:

The villi are a specialized structure within the small intestine that plays a crucial role in the absorption of nutrients. They are formed by the intricate arrangement of different tissues and cells, which work together to achieve this essential function.