Onion epidermal cell

The epidermal cells of onions provide a protective layer against viruses and fungi that may harm the sensitive tissues.

Because of their simple structure and transparency they are often used to introduce students to plant anatomy[1] or to demonstrate plasmolysis.

[2] The clear epidermal cells exist in a single layer and do not contain chloroplasts, because the onion fruiting body (bulb) is used for storing energy, not photosynthesis.

The vacuole is prominent and present at the center of the cell, surrounded by cytoplasm.

Light microscopes are typically used for observing onion cells.