Clearing of keratin-containing material can be accelerated by which step?

• A. Extend clearing time
• B. Use alcohol
• C. Use more KOH
• D. Heat may accelerate clearing

Answer: (D)

Clearing keratin-containing material relies on breaking down the tough keratin with a clearing agent such as potassium hydroxide. Heating speeds this digestion by increasing the reaction rate and helping the reagent penetrate the keratin matrix, so the tissue becomes transparent more quickly without needing to extend the process unnecessarily. Extending clearing time would help, but it’s slower; using more KOH could speed clearing but risks over-clearing or damaging the sample; alcohol isn’t an effective method for accelerating keratin clearing and can interfere with visualization.