The epithelial tissue rests upon a non-cellular______.

Explanation

**Step-by-Step Solution:**

1. **Understanding Epithelial Tissue**: Epithelial tissue is a type of tissue that serves various functions, including protection, secretion, and absorption. It is found in many parts of the body, including the skin, lining of organs, and cavities.

2. **Position of Epithelial Tissue**: Epithelial tissues are always found on top of other tissues. The prefix "epi-" means "above," indicating that these tissues are positioned above another layer.

3. **Non-Cellular Component**: The question specifically asks for a non-cellular component that epithelial tissue rests upon. This indicates that the answer must refer to a structure that does not consist of cells.

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