Which problem is associated with tissue drying before coverslipping?

• A. Tissue drying before coverslipping
• B. Overhydration
• C. Excessive staining
• D. Bubbles under the slide

Answer: (A)

Drying artifacts occur when a stained tissue section is allowed to dry before applying the coverslip. As water and solvents evaporate, the section shrinks and becomes brittle, leading to cracks, folds, and even detachment from the slide. These physical changes distort morphology and create uneven surfaces, making it hard for mounting medium to wet the tissue properly and for the coverslip to sit flat. In short, the key problem is the mechanical damage and poor adhesion caused by drying, which directly degrades microscopic quality. Other issues listed would arise from different problems—overhydration causes swelling and halo artifacts, excessive staining alters color intensity, and bubbles under the slide come from air entrapment during mounting rather than drying artifacts.