The immune system can be said to have a "memory" because:

Question

Quizplus · Accepted Answer

Once the immune system encounters an antigen, it will produce memory cells that can recognize and respond to that antigen more quickly and effectively in the future. This is how vaccines work - by introducing a harmless version of an antigen to the immune system, it can develop memory cells without causing illness, so that if the actual pathogen is encountered later, the immune response is more efficient.

The Immune System Can Be Said to Have a "Memory