Which mechanism is a key feature of innate immunity?

The mechanism that is a key feature of innate immunity is barrier defenses like skin. Innate immunity is the body’s first line of defense against pathogens and is characterized by its rapid response to invasions. Barrier defenses, including the skin and mucous membranes, serve as physical and biochemical barriers that prevent pathogens from entering the body.

These barriers provide a non-specific defense mechanism that is always present and ready to act, unlike adaptive immunity, which develops a specific response to particular pathogens and involves memory cell development and the production of antibodies. Adaptive responses take longer to initiate and rely on the previous exposure to pathogens. Since innate immunity functions immediately upon exposure to pathogens without requiring prior sensitization, barrier defenses are essential to protect the body from infections effectively.