Final answer:
The body's defense against infection is primarily provided by the immune response, which includes both the innate and the adaptive immune systems. The innate response offers immediate, non-specific defense mechanisms, while the adaptive response is slower but targets specific pathogens.
Step-by-step explanation:
The body's defense against infection is predominantly handled by the immune response, which includes various layers of protection, starting with physical barriers like the skin and mucous membranes that act instantly to prevent pathogen invasion. Beyond these initial defenses, we have the innate immune response, which involves non-specific defense mechanisms responding rapidly to pathogenic invaders. Yet, it is the adaptive immune response that delivers a more targeted and effective attack against infections, thanks to the sophisticated actions of B cells and T cells that remember and respond to specific pathogens.
The body's immune system is designed to tackle pathogens through barrier defenses and immune responses. These include physical and chemical barriers such as tears that contain microbicidal factors, which act as part of the innate immune response to reduce the workload of the adaptive immune response in combating infections.