In some cases, looking at a living cell under a microscope can cause it damage or worse, can kill it. Now, a new kind of microscope has been invented by researchers from the Howard Hughes Medical Institute that is able to non-invasively take a three dimensional look inside living cells with stunning results. The device uses a thin sheet of light like that used to scan supermarket bar codes and could help biologists to achieve their goal of understanding the rules that govern molecular processes within a cell.
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http://www.gizmag.com/3d-microscope-movies-living-cells/18138/This is really great news!