Final answer:
Adaptive immunity is an immunity that develops after the body's exposure to a specific pathogen or vaccination, creating a long-term defensive memory through antibodies and memory cells.
Step-by-step explanation:
The type of immunity described is adaptive immunity, which develops after the body is exposed to an antigen, such as a pathogen or through vaccination. When first exposed to an invader like a virus, the immune system creates antibodies that are specific for that particular pathogen. The adaptive immune system, consisting of T and B cells, mobilizes to remember the pathogen and creates a rapid and powerful response to subsequent exposures, providing the body with long-term protection against the same type of pathogen. This is the body's more sophisticated line of defense that involves a memory component, distinguishing it from innate immunity, which provides immediate, but nonspecific responses to pathogens.
Active immunity is a result of the adaptive immune system's response, resulting in the formation of memory cells that lead to long-lasting protection against reinfection by the same pathogen. In contrast, passive immunity is the temporary protection provided by transferring antibodies from another source, without the activation of one's own adaptive immune response.