Acetic acid is an excellent nuclear fixative.

• A. True
• B. False
• C. It fixes lipids as well
• D. It is not used as a fixative

Answer: (A)

Preserving nuclear detail relies on how quickly and how proteins and nucleic acids are fixed. Acetic acid acts as a coagulative fixative, rapidly denaturing and precipitating proteins, including those in the nucleus. This quick action helps maintain crisp chromatin and nuclear outlines, and it often swells the nucleus slightly, which enhances visibility of nuclear details. Because of this property, acetic acid is valued as an excellent nuclear fixative, especially as the active component in fixatives like Carnoy’s solution. It doesn’t fix lipids well; lipids are handled better by other reagents or solvent-based methods, so the idea that it fixes lipids isn’t accurate.