During keratinization, what happens to new cells?

During keratinization, new cells transition into a tougher, protective form by filling with the protein keratin. This process primarily occurs in the outer layer of the skin, known as the epidermis. As the cells move from the lower layers to the surface, they undergo a transformation where they essentially lose moisture and accumulate keratin. This protein is essential as it provides strength and waterproofing to the skin, helping maintain its barrier function against environmental damage.

As these keratin-filled cells continue to rise toward the surface, they eventually die and form a protective layer, which ultimately results in the shedding of dead skin cells. The filling of new cells with keratin is critical for skin health, ensuring the skin remains resilient and able to protect the underlying tissues from harm. This makes the option regarding the filling with protein the accurate representation of what happens to new cells during keratinization.