Onion epidermal cells are clear and do not contain chloroplasts. This is because the onion grows as a bulb and is used by the plant for energy storage and does not participate in photosynthesis. Epidermal cells are structured in a single layer with rigid cell walls.
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Explore the subject by using the + and - buttons to zoom in and out. The image will load more tiles as more zoom is used. This is indicated by a loading icon that will appear under the Full Screen Button which is located below the zoom out button. To get an unobstructed view of the specimen click the layers button on the upper right. This will allow you to select full specimen. Full specimen mode allows for more zoom.
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Version 6.0 - VML Multiverse View