What is the primary purpose of formalin in pathology?

What is the primary purpose of formalin in pathology?

• A. Preservation of tissue
• B. Disinfection of instruments
• C. Sterilization of waste
• D. Staining tissues

Answer: (A)

Formalin’s main function is to fix and preserve tissue. By cross-linking proteins, it stops enzymatic activity and prevents autolysis and decomposition, locking in the tissue’s cellular and structural detail. This stabilization is essential for the subsequent processing steps (dehydration, clearing, paraffin embedding) and for staining later, so the pathologist can examine the tissue accurately under the microscope. It isn’t used to disinfect instruments or sterilize waste, which require other methods, and it isn’t a stain—the staining occurs after fixation to provide contrast for analysis.

Formalin’s main function is to fix and preserve tissue. By cross-linking proteins, it stops enzymatic activity and prevents autolysis and decomposition, locking in the tissue’s cellular and structural detail. This stabilization is essential for the subsequent processing steps (dehydration, clearing, paraffin embedding) and for staining later, so the pathologist can examine the tissue accurately under the microscope. It isn’t used to disinfect instruments or sterilize waste, which require other methods, and it isn’t a stain—the staining occurs after fixation to provide contrast for analysis.