Why is a skin cell different from a muscle cell

Skin cell serves a completely different purpose. Muscle cells have large amount of mitochondria in them and are energy rich to perform functions that require movement. They are more durable than epithelial cells. Epithelial cells (skin cells) are quickly shed, quickly replaced, lack mitochondria and are mass produced by the body.

Why is muscle skin by skin is a type of color and muscle is a cell