What consequence can occur if tissue is not completely fixed before dehydration, leading to changes at the center of the tissue?

• A. Increased eosinophilia at the center
• B. Increased basophilia at the center
• C. Crystallization of tissue
• D. No change

Answer: (A)

When tissue isn’t fully fixed before dehydration, the center of a thicker specimen can remain under-fixed. During dehydration and embedding, enzymes in the tissue continue to act, causing autolysis and protein denaturation in that central region. This breakdown of nucleic acids reduces basophilic staining (which highlights DNA and RNA), while denatured proteins take up the eosin dye more readily, making the center appear more eosinophilic (pink/red) under the stain. That’s why increased eosinophilia at the center is the expected consequence. Crystallization isn’t a typical artifact of this process, and basophilia wouldn’t increase in this scenario; there would be noticeable changes rather than no change.