College of Massage Therapists of British Columbia (CMTBC) Practice Exam

Which type of epithelial cells are keratinized?

1. Simple cuboidal

2. Simple columnar

3. Stratified squamous

4. Transitional

The correct answer is: Stratified squamous

Keratinized epithelial cells are primarily found in stratified squamous epithelium. This type of epithelium consists of multiple layers of cells, with the top layers being flat and often filled with keratin, a tough, protective protein. The presence of keratin helps to create a barrier against environmental insults, such as pathogens and physical abrasion, while also reducing water loss. In areas such as the skin, the outer layer is composed of dead keratinized cells that provide durability and water-proofing, which is essential for protecting underlying tissues. This contrasts with other types of epithelium, such as simple cuboidal, simple columnar, and transitional epithelium, which do not have a keratinized structure and serve different functions, such as secretion, absorption, or accommodating stretching in the case of transitional epithelium.