American Sign Language (ASL) is a natural language that serves as the predominant sign language of Deaf communities in the United States and most of anglophone Canada.
Adaptive immunity refers to antigen-specific immune response. The adaptive immune response is more complex than the innate. The antigen first must be processed and recognized. Once an antigen has been recognized, the adaptive immune system creates an army of immune cells specifically designed to attack that antigen.
adaptive responses are highly specific to the particular pathogen that induced them, and they provide long-lasting protection. A person who recovers from measles, for example, is protected for life against measles by the adaptive immune system, although not against other common viruses, such as those that cause mumps or chickenpox.