Adaptive (acquired) immunity refers to: a) Antigen-nonspecific defense mechanisms that a host uses immediately or within several hours after exposure...

Adaptive (acquired) immunity refers to:

a) Antigen-nonspecific defense mechanisms that a host uses immediately or within several hours after exposure to an antigen. This is the immunity one is born with and is the initial response by the body to eliminate microbes and prevent infection

b) Antigen-specific defense mechanisms that take several days to become protective and are designed to react with and remove a specific antigen. This is the immunity one develops throughout life