"stratum corneum"的定义和意义

What is "stratum corneum"?

The stratum corneum, also known as the horny layer, is the outermost layer of the epidermis. It consists of flattened, dead skin cells called corneocytes that are tightly packed together. This layer acts as a protective barrier against external factors such as bacteria, moisture loss, and physical damage. The stratum corneum helps maintain the skin's hydration, prevents the entry of harmful substances, and contributes to the skin's overall strength and elasticity. It is continuously shed and replaced by new cells from the underlying layers.