Which structures are included in the integumentary system?

• A. Skin, hair, nails, sweat glands, sebaceous glands, and nerve receptors
• B. Bones and joints
• C. Lungs and airways
• D. Digestive organs

Answer: (A)

The structures that form the outer protective covering and sensory interface of the body are part of the integumentary system. It includes the skin as the primary organ, plus hair, nails, sweat glands, sebaceous glands, and nerve receptors in the skin. Skin serves as a barrier and helps regulate temperature; sweat glands produce perspiration to cool the body; sebaceous glands secrete oils to keep skin and hair moisturized; hair and nails provide protection and support; nerve receptors detect touch, pressure, temperature, and pain. Altogether, these components protect against infection, aid in temperature control, and provide sensory information about the environment.

Bones and joints belong to the skeletal system; lungs and airways belong to the respiratory system; digestive organs belong to the digestive system.