Epithelium is a type of tissue that forms the outermost layer of the body’s organs, as well as the inner lining of cavities and surfaces throughout the body. It serves as a protective barrier and can have various shapes and functions depending on its location, such as absorbing nutrients in the intestines, secreting mucus in the respiratory tract, or providing a protective layer for the skin.
Usage: “The epithelium of the skin acts as a protective barrier against external factors, while the epithelium in the small intestine is specialized for nutrient absorption.”
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