Which is NOT a function of the integumentary system?

• A. Protection
• B. Sensation
• C. Temperature regulation
• D. Hormone balance

Answer: (D)

The skin, as part of the integumentary system, mainly serves as a protective barrier, a sensory interface, and a regulator of body temperature. It protects underlying tissues from injury and infection, houses receptors that sense touch, pressure, temperature, and pain, and uses sweat and blood flow to help control heat loss or retention. It also participates in excretion through sweat and can synthesize vitamin D with sun exposure, which contributes to mineral balance. Hormone balance, however, is controlled by the endocrine system, not by the skin, so the statement about hormone balance is not a function of the integumentary system.