Which term refers to skin protection against infection as a function of a system?

• A. Integumentary System
• B. Musculoskeletal System
• C. Cartilage
• D. Organ System

Answer: (A)

Protection against infection is a function of the integumentary system. This system includes the skin and its associated structures, forming the body's external barrier that blocks pathogen entry. It provides chemical defenses (like the acidic skin environment and antimicrobial substances), supports immune responses in the skin, and aids in wound healing when needed. The other options point to different concepts—bones, muscles, and joints for the musculoskeletal system; cartilage as a tissue; and organ system as a broad category—none of which specifically describe the skin’s protective barrier against infection.