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Pictures in the Banner





* This mystery structure was ALIVE at the time of the photo. A very lively cell, indeed! This is a picture of epithelial cells from a living fish embryo.

* This image was taken through a microscope, and represents a very, very tiny portion of the whole organism. The pentagon you can see is a single skin cell. The large black circle in the center is the nucleus.

* In real life, the field of view is approximately 100 micrometers across.

* The organism had been stained with a special fluorescent lipid (= fat).The membranes in cells are made of lipids. A fluorescent lipid may partition into specific membranes.

* The lipid was very selective, and only stained a very special part of the organism. This lipid, DiOC6, is selective for the mitochondrial membranes. Therefore, the white lines you see in the mystery photo are chains of mitochondria, each one lit up because the fluorescent lipid found its way to the mitochondrial membranes.

* The very special part is something that every introductory biology student "meets" in her high school class, when learning about "The Cell". The mitochondria are often called "the powerhouses of the cell" because of their role in energy conversion. What is most exciting about this picture is the fact that this one cell has thousands of mitochondria. It is very common for cells to have many, many mitochondria. In fact, as you walk around you should feel quite zippy with energy, knowing that most of your body cells have thousands of these organelles inside!

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