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"Epithelial tissue is composed of tightly connected cells arranged in one or more layers. Epithelial tissues covers the whole surface of the body (it's your skin!) as well as lining all cavities and forming glands. Epithelial tissues as many functions including protection, sensation, diffusion, secretion, absorption and excretion." http://www.hartnell.edu/tutorials/biology/tissues.html

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from Education.com

Summer Learning Loss: The Problem and Some Solutions

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