New Mexico Cosmetology Practice Exam 2025 – All-in-One Guide to Mastering Your Certification!

Sebaceous glands play a vital role in the health and maintenance of the skin and hair by producing an oily substance known as sebum. This oil is crucial because it acts as a natural moisturizer, keeping the skin hydrated and preventing dryness. Sebum also helps to lubricate the hair, making it appear shiny and reducing brittleness. Moreover, the oil produced by sebaceous glands has antibacterial properties, which can help to protect the skin from certain infections.

The other functions mentioned, such as sweating or protecting against UV rays, are performed by different parts of the integumentary system, like sweat glands for perspiration and melanocytes for UV protection. Additionally, while the skin does aid in temperature regulation through mechanisms like sweating, that function is not directly related to the role of sebaceous glands. Therefore, the primary and most significant function of sebaceous glands is their ability to produce oil that lubricates both hair and skin, making option C the correct choice.