Final answer:
Sebum, produced by sebaceous glands, serves protective functions such as containing anti-microbial properties, providing a physical barrier, and preventing water loss from the skin. It lubricates the skin and hair but does not protect from UV light. The correct choices are options a, b and c.
Step-by-step explanation:
The protective functions of sebum, which is produced by the sebaceous glands, include several key roles:
- Sebum contains anti-microbial compounds that prevent the growth of microorganisms on the skin.
- It provides a physical barrier which protects the skin from being penetrated by potentially harmful bacteria and other pathogens.
- Sebum plays a crucial role in the prevention of water loss from the skin by waterproofing the skin and hair, particularly in low-humidity environments.
While sebum does contain lipids that help inhibit microbial growth, it also provides certain microbes with nutrients. Moreover, sebum is involved in the lubrication of the hair and hair follicle, maintaining skin and hair pliability and moisture. However, it does not protect from UV light; this function is mainly fulfilled by melanin within the skin.