how does the integumentary system keep the body safe

The integumentary system keeps the body safe primarily by acting as a physical and biochemical barrier. It protects internal tissues and organs from environmental hazards like bacteria, viruses, chemicals, temperature extremes, and UV radiation. The skin's outermost layer (epidermis) forms a tough barrier reinforced by dead keratinized cells, preventing pathogens and foreign substances from entering the body. The dermis supports the epidermis with blood supply and nerves for danger detection. The hypodermis cushions internal organs from mechanical trauma. Additionally, the system produces antimicrobial peptides and oils that destroy bacteria on the skin surface and activates immune responses if necessary. Other safety mechanisms include wound healing processes that clot blood and regenerate skin to prevent infection, temperature regulation through sweating and blood vessel dilation/constriction, and sensory detection of harmful stimuli such as pain or temperature. Hair and nails provide further protection to sensitive areas and help filter particles. Moreover, the integumentary system synthesizes vitamin D which supports overall health including bone protection.