This is an image of the epidermal layer of a green onion from Caltech’s open kitchen, taken 4/18/19 at 5PM. The sample was obtained by cutting and removing the thin, membrane-like layer between the thicker layers of the green onion. The layer was placed onto a slide with some water, and observed using the Foldscope. The elongated epidermal cells of the onion (Allium Fistulosum) can clearly be seen in the image. The cells are transparent and come in a single layer, which makes them easy to discern with the Foldscope. The tissue does not contain chloroplasts because the body of the onion is used for energy storage rather than photosynthesizing.

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