Which layer of the epidermis contains keratin intermediate filaments?

The stratum corneum is indeed the correct layer of the epidermis that contains keratin intermediate filaments. This outermost layer consists of dead skin cells that have been filled with keratin, a fibrous protein that provides the skin with its protective features. The keratin filaments in these cells contribute to the waterproofing and barrier functions vital for maintaining skin integrity and preventing water loss.

In contrast, while the stratum granulosum also contains keratinocytes and is involved in the process of keratinization, it primarily contains keratohyalin granules that assist in binding keratin filaments together rather than a high concentration of keratin intermediate filaments. The stratum basale, as the deepest layer, is responsible for the proliferation of new skin cells and does not primarily contain keratin; instead, it contains basal keratinocytes that will eventually move up and undergo keratinization. The stratum lucidum is found only in thick skin areas and serves to provide an additional barrier but is not characterized by a significant presence of keratin intermediate filaments as its primary feature.