The lack of an immune response to a foreign compound entering the body is called "tolerance." This phenomenon can occur naturally, as in the case of self-tolerance, where the immune system does not attack the body's own tissues. It can also be induced artificially, such as in the context of organ transplants or certain therapies, where the goal is to prevent an immune response against a foreign substance.
antibodies
An immune response is based on the ability to distinguish molecules that are part of the body ("self") from those that are not ("nonself," or foreign). Such molecules that can elicit an immune response are called antigens.
denial of entry
Foreign invaders have proteins called antigens that are recognized by the immune system as non-self. This recognition triggers an immune response to eliminate the invading pathogen.
The disorder caused by the body's exaggerated response to foreign chemicals and proteins is called an allergy. Symptoms can range from mild reactions like itching and sneezing to severe reactions like anaphylaxis.
Antigen
Proteins that destroy foreign substances are called antibodies. Antibodies are produced by the immune system in response to the presence of antigens, such as bacteria and viruses, to help eliminate these foreign invaders from the body.
'Foreign' chemicals which get into the blood and provoke an immune response are called antigens.
The hair that grows under the nose is called the nasal hair. The function of the nasal hair is to prevent foreign particles and insects from entering the nose.
Antigenan·ti·gen/ˈantijən/Noun:A toxin or other foreign substance that induces an immune response in the body, esp. the production of antibodies.
Depending on the exact response, the substance is generally called a pathogen, yet more specifically depending on the nature of the response and origin of the substance, could be an antigen, allergen, carcinogen, etc.
The inflammatory response is called a general defense because the response is similar regardless of the pathogen. It is a fundamental response of the body to injury and disease."Because the inflammatory response is the same no matter what the pathogen, it is called the body's general defense." Quoted from: Texas Science Explorer Grade 7 (textbook), published by Prentice Hall "Because the inflammatory response is the same no matter what the pathogen, it is called the body's general defense." Quoted from: Texas Science Explorer Grade 7 (textbook), published by Prentice Hall