Cellularity as the name suggests means that the epithelium is made up almost entirely of cells. In other types of tissue the cells are spread far apart and are separated by lots of extracellular material. Another key characteristic of epithelial tissue is polarity. read more
Epithelial tissue is composed of cells laid together in sheets with the cells tightly connected to one another. Epithelial layers are avascular, but innervated. Epithelial cells have two surfaces that differ in both structure and function. read more
3 classes 1. simple endoderm1 layer, few think upper layers dermisa. squamousb. cuboidalc. columman 2. read more