What characterizes active immunity?

Active immunity is characterized by long-term protection from antibodies. This occurs when an individual's immune system is exposed to a pathogen and produces its own antibodies in response. This can happen through natural infection or through vaccination. The body not only produces antibodies but also creates memory cells that remember the pathogen, allowing for a quicker and more effective response if the same pathogen is encountered again in the future. This is in contrast to passive immunity, where antibodies are transferred from another source and do not create a lasting immune memory. Hence, the duration and efficacy of protection provided by active immunity emphasize its significance in long-term defense against diseases.