What does our body have built in to prevent the entrance of pathogens?

The body has multiple systems functioning as protective mechanisms to prevent pathogens from entering and causing infections. These mechanisms encompass both physical barriers, like the skin and mucous membranes, and biological responses, which include the actions of immune cells that detect and eliminate threats.

Protective mechanisms not only block the entry of harmful microorganisms but also include the inflammatory response, which helps to contain infections and begin the healing process. This term captures the broad array of actions and processes that the body employs to safeguard against pathogens, highlighting the complex, integrated response that is critical for maintaining health.

While protective barriers specifically refer to the physical aspects of defense, and immune responses and antibodies focus on the biological reactions after a pathogen has been encountered, protective mechanisms cover the entire spectrum of defenses the body has in place to preemptively thwart the entrance of harmful agents. This holistic perspective is what makes the term most fitting in the context of the question.