Which components are included in the integumentary system?

• A. Skin, hair, nails, and glands.
• B. Bones, muscles, and tendons.
• C. Lungs, trachea, and alveoli.
• D. Heart, arteries, and veins.

Answer: (A)

The main concept here is what the integumentary system consists of. It includes the skin and its appendages: hair, nails, and glands, along with the sensory receptors in the skin. Skin forms a protective barrier, helps regulate body temperature, and provides sensation. Hair and nails are keratinized structures that grow from the skin and contribute to protection and tactile perception. Glands, including sweat glands for cooling and sebaceous glands for lubrication and antimicrobial protection, are essential parts of this system and support its protective and regulatory roles.

Other groups listed belong to different body systems: bones, muscles, and tendons are part of the musculoskeletal system; lungs, trachea, and alveoli are part of the respiratory system; and the heart, arteries, and veins are part of the cardiovascular system. Therefore, the components that make up the integumentary system are skin, hair, nails, and glands.