Osmium tetroxide is used for lipids in frozen sections and is associated with which type of microscopy?

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Multiple Choice

Osmium tetroxide is used for lipids in frozen sections and is associated with which type of microscopy?

Osmium tetroxide is a heavy metal fixative that binds to lipids, especially in membranes, and becomes highly electron-dense. This makes lipid-rich structures standout under electron beams, which is why osmium is used to preserve and visualize lipids in frozen (cryosections) and other EM specimens. The imaging mode that most relies on such heavy-atom contrast and surface detail is secondary electron microscopy, where the surface topology is revealed with the enhanced contrast provided by osmium staining of lipids. Therefore, this use is associated with secondary electron microscopy. It is not used to stain nucleic acids in paraffin sections, nor to fix calcium deposits, nor as a primary stain for proteins.

Osmium tetroxide is a heavy metal fixative that binds to lipids, especially in membranes, and becomes highly electron-dense. This makes lipid-rich structures standout under electron beams, which is why osmium is used to preserve and visualize lipids in frozen (cryosections) and other EM specimens. The imaging mode that most relies on such heavy-atom contrast and surface detail is secondary electron microscopy, where the surface topology is revealed with the enhanced contrast provided by osmium staining of lipids. Therefore, this use is associated with secondary electron microscopy. It is not used to stain nucleic acids in paraffin sections, nor to fix calcium deposits, nor as a primary stain for proteins.

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