Stratum corneum

Definition

The stratum corneum is the outermost layer of the epidermis, composed mainly of dead keratinized cells. It acts as a barrier to protect underlying tissues from infection, dehydration, and physical harm.

5 Must Know Facts For Your Next Test

1. The stratum corneum consists primarily of dead keratinized cells that are continuously shed and replaced.
2. It has a crucial role in maintaining skin hydration by preventing water loss.
3. This layer provides a first line of defense against microbial invasion.
4. The thickness of the stratum corneum varies depending on the body part, being thickest on the palms and soles.
5. Lipids within this layer contribute to its barrier function and antimicrobial properties.

Review Questions

Related terms

Epidermis:

The outermost layer of skin consisting of multiple sublayers including the stratum corneum.

Keratinocytes:

Cells that produce keratin and make up most of the epidermal cells.

Sebum:

An oily substance produced by sebaceous glands that helps lubricate and protect the skin.