Onion epidermis with large cells under light microscope. Clear epidermal cells of an onion, Allium cepa, in a single layer. Each cell with wall, membrane, cytoplasm, nucleus and large vacuole. Photo. Shutterstock Image - Onion epidermis with large cells under light microscope. Clear epidermal cells of an onion, Allium cepa, in a single layer. Each cell with wall, membrane, cytoplasm, nucleus and large vacuole. Photo. - ID: 603422597