Cosmetology Practice Test – Pass the Massachusetts State Board Exam (2025 Guide)

The oil produced by sebaceous glands, known as sebum, plays an essential role in maintaining the health and appearance of hair. This natural oil helps to coat the hair shaft, which provides a protective layer that can prevent moisture loss. As a result, the presence of sebum adds shine to the hair, making it look healthy and vibrant. Additionally, this oil helps to keep the hair pliable, reducing the likelihood of breakage and frizz, as it provides a level of conditioning. By fulfilling these functions, the oil acts as a natural barrier against environmental elements while also enhancing the overall aesthetics of the hair.

In contrast, the other options do not accurately represent the effects of sebum on hair. While some may think that sebaceous oil could lead to dryness or tangling, it actually serves to moisturize and protect the hair. Accelerated hair loss is also unrelated to sebum, as it is influenced by various factors such as genetics, health, and stress, rather than the natural oils produced by the scalp.