Answer:
When a person contracts a disease, their immune system responds by producing specific antibodies and other immune cells to fight off the infection. The immune system also develops a "memory" of the infection, which allows it to respond more quickly and effectively if the person is exposed to the same disease in the future.
After the person recovers from the disease, their immune system retains the memory of the infection and the antibodies and immune cells remain in their body, ready to respond if the person is exposed to the disease again. This is known as immunity.
Depending on the disease, the immunity may be short-term or long-term. For some diseases, the person may be immune for the rest of their life, while for others the immunity may fade over time and they may be susceptible to the disease again in the future.
In general, the immune system is a complex and highly adaptive system that allows the body to protect itself against a wide variety of pathogens and diseases. It is able to learn from past infections and use that knowledge to better defend against future infections
Step-by-step explanation: