the immune response
Like the immune systems of other vertebrates, the human immune system is adaptive. If pathogens manage to get through the bodys first two lines of defense, the third line of defense takes over. The third line of defense is referred to as the immune response . This defense is specific to a particular pathogen, and it allows the immune system to remember the pathogen after the infection is over. If the pathogen tries to invade the body again, the immune response against that pathogen will be much faster and stronger.