Which statement correctly describes Osmium tetroxide's role in histology?

Which statement correctly describes Osmium tetroxide's role in histology?

• A. It is used to stain lipids
• B. It stains nucleic Acids
• C. It stains collagen fibers
• D. It stains carbohydrates

Answer: (A)

Osmium tetroxide is used in histology primarily because it reacts with the unsaturated bonds in lipids, fixing and staining them so they become electron-dense and appear dark. This makes lipid-rich structures like cell membranes and myelin stand out clearly under microscopy, which is why it’s chosen as a lipid stain and fixative. Nucleic acids, collagen fibers, and carbohydrates are not specifically targeted by Osmium tetroxide; they require different stains or methods to visualize them.

Osmium tetroxide is used in histology primarily because it reacts with the unsaturated bonds in lipids, fixing and staining them so they become electron-dense and appear dark. This makes lipid-rich structures like cell membranes and myelin stand out clearly under microscopy, which is why it’s chosen as a lipid stain and fixative. Nucleic acids, collagen fibers, and carbohydrates are not specifically targeted by Osmium tetroxide; they require different stains or methods to visualize them.