Answer: sebum does not slow water loss from the skin during low humidity conditions, but it does protect the skin from bacteria, lubricate the skin, and provide some protection against the damaging effects of UV radiation.
Step-by-step explanation:
Sebum is an oily substance produced by the sebaceous glands in the skin. It serves multiple functions to help maintain the health and integrity of the skin.
The correct functions of sebum are:
1. Protect the skin from bacteria: Sebum contains antimicrobial properties that help prevent the growth of harmful bacteria on the skin. It creates a slightly acidic environment that inhibits the growth of bacteria and other microorganisms.
2. Lubricate the skin: Sebum helps keep the skin soft and supple by lubricating the surface. It prevents excessive dryness and helps maintain the skin's natural moisture balance.
3. Protect the skin from the damaging effects of UV radiation: Sebum provides a degree of protection against the harmful effects of ultraviolet (UV) radiation from the sun. It acts as a natural barrier, absorbing and scattering some of the UV rays before they reach the deeper layers of the skin.
However, sebum does not play a significant role in slowing water loss from the skin during low humidity conditions. Instead, the outermost layer of the skin, called the stratum corneum, acts as the primary barrier to water loss. It consists of dead skin cells and lipids that form a protective barrier, reducing water loss from the skin.