What process do keratinocytes undergo as they move to the surface of the skin?

Keratinocytes undergo a process known as keratinization as they move towards the surface of the skin. This is a vital biological process where keratinocytes, which are the predominant cells in the epidermis, produce keratin, a tough, protective protein. As these cells migrate from the deeper layers of the epidermis towards the surface, they undergo changes that result in them becoming more flattened and hardened. This transformation is crucial for the formation of the outer protective layer of the skin, which helps to prevent water loss and protect underlying tissues from damage, pathogens, and environmental factors.

As keratinization progresses, the keratinocytes gradually lose their nuclei and organelles, producing a dense, keratin-rich environment. This process ultimately contributes to the skin's barrier function and is essential for maintaining overall skin health. The completed keratinized layer eventually sheds off in a process called desquamation, allowing for continuous renewal of the skin's surface. This cycle is part of the skin's natural regenerative process, which is essential for healing and protecting the body.