Epithelial cell
Epithelial cells were s from the lining of the Human stomach. The cells were relatively un-differentiated and non-specialized, a fact that made them ideal for the purposes of cloning.

In 2153, Doctor Phlox's study of the Xindi pilot's corpse's epithelial cells identified scales which later confirmed he was Xindi-Reptilian. ()

In 2365, William T. Riker and Katherine Pulaski had some of their epithelial cells stolen so that they could   by the Mariposans. ()

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Anatomy