What does hyperkeratosis refer to?

• A. The thinning of the skin caused by a mass of keratinocytes
• B. The thickening of the skin caused by a mass of keratinocytes
• C. Increased oil production in the sebaceous glands
• D. A temporary redness of the skin after irritation

Answer: (B)

Hyperkeratosis is a thickening of the outermost layer of the skin, the stratum corneum, due to increased keratin production or slowed shedding of keratin. This produces tougher, thicker skin, like a callus, as a protective response to friction or irritation. So describing the skin as thickening because of keratin buildup fits the concept. It’s not thinning of the skin, not increased oil production, and not a temporary redness from irritation.