Which of the following is a true statement regarding sebaceous glands?

• A. They primarily function in thermoregulation by producing sweat.
• B. They are classified as apocrine glands.
• C. They are most abundant on the palms of the hands and soles of the feet.
• D. They secrete sebum to lubricate and waterproof the skin and hair.

Answer: (D)

Verified step by step guidance

1. Understand the function of sebaceous glands: Sebaceous glands are specialized exocrine glands in the skin that produce and secrete sebum, an oily substance that helps lubricate and waterproof the skin and hair.
2. Clarify the role of sebaceous glands in thermoregulation: Sebaceous glands do not primarily function in thermoregulation. Sweat glands, particularly eccrine glands, are responsible for thermoregulation by producing sweat.
3. Differentiate sebaceous glands from apocrine glands: Sebaceous glands are classified as holocrine glands, not apocrine glands. Holocrine secretion involves the rupture of the entire cell to release its contents, whereas apocrine glands release their secretions by budding off portions of the cell.
4. Identify the distribution of sebaceous glands: Sebaceous glands are not most abundant on the palms of the hands and soles of the feet. In fact, these areas lack sebaceous glands entirely. Sebaceous glands are most commonly found in areas with hair follicles, such as the scalp, face, and upper body.
5. Confirm the correct statement: The true statement regarding sebaceous glands is that they secrete sebum to lubricate and waterproof the skin and hair, which is essential for maintaining skin health and preventing dryness.