Tennessee Barber Practice Exam

Oily skin and blackheads are the result of over-active sebaceous glands, not salivary, thyroid, or sudoriferous glands. This is because sebaceous glands are responsible for producing sebum, an oily substance that protects and lubricates the hair and skin. When these glands produce too much sebum, it can clog pores and lead to the formation of blackheads and acne. Salivary glands, on the other hand, produce saliva in the mouth; thyroid glands regulate metabolism; and sudoriferous glands produce sweat to regulate body temperature. None of these glands are directly involved in the production of sebum, making them incorrect options. Overall, the over-activity of sebaceous glands is the primary cause of oily skin and blackheads.