Answer
Epithelium usually consists of one or more layers of closely packed cells. The outer surface of this type of tissue is usually exposed to the exterior, or faces an internal space of the body. Epithelia are usually avascular, and the cells are tightly bound by tight junctions. This tissue is able to grow and function because of underlying connective tissue: the connective tissue vasculature brings nutrients and oxygen to the epithelium, and removes waste and carbon dioxide.
Work Step by Step
The epithelial basement membrane attaches it to deeper body tissues/structures
