Epithial tissues are the protective animal tissues. They occur in the form of sheets that have one free surface. Epithelium occurs as a protective covering all over the body and it also covers all the body organs. It forms the outermost layer of the skin. It lines buccal cavity, pharynx, oesophagus, stomach, nose, air tubes, lungs and blood vessles.
Epithelial cells are closely packed. They do not have intercellular spaces.
The cell to cell contact binds the cell together.
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