Acetic acid is described as which type of fixative and what does it do?

• A. Non-coagulant fixative that fixes only nucleoprotein and does not fix carbs or lipids, precipitates DNA, lyses RBCs
• B. Coagulant fixative that fixes carbohydrates
• C. Crosslinks proteins
• D. Preserves lipids

Answer: (A)

Acetic acid is a non-coagulant fixative. That means it does not cause proteins to coagulate or crosslink; instead it preserves certain components by precipitating nucleoproteins and nucleic acids. It particularly fixes nucleoproteins and DNA while not fixing carbohydrates or lipids, and its acidic action can disrupt cell membranes, causing red blood cells to lyse. This is why the description that it is a non-coagulant fixative that fixes nucleoprotein and does not fix carbohydrates or lipids, precipitates DNA, and lyses RBCs matches how acetic acid behaves in tissue fixation.