Final answer:
Epithelial tissues can be classified based on the shape of the cells and the number of cell layers. The different shapes include squamous, cuboidal, and columnar. The number of layers can be one (simple epithelium) or more than one (stratified epithelium).
Step-by-step explanation:
Epithelial tissues can be classified based on the shape of the cells and the number of cell layers. The different cell shapes include squamous (flattened and thin), cuboidal (boxy), and columnar (rectangular and taller than wide).
The number of cell layers can be one, forming a simple epithelium, or more than one, forming a stratified epithelium. There are also pseudostratified and transitional epithelial tissues.