The problem shown in the image is most likely caused by which factor?

• A. Slow freezing
• B. Overdecalcification
• C. Underfixation
• D. Incomplete embedding

Answer: (A)

When tissue is frozen for sectioning, water inside cells forms ice crystals. If freezing is slow, these crystals grow large and push apart cellular structures, creating large clear spaces and a disrupted, jagged appearance. That ice crystal artifact is what’s being shown, so slow freezing is the most likely cause. Rapid freezing minimizes crystal size and preserves tissue morphology, reducing this problem.

Other factors would produce different issues: overdecalcification alters staining and detail in mineralized tissue; underfixation leads to poor preservation and weaker staining; incomplete embedding causes infiltration problems and edge artifacts.