NEET BIOLOGY

Detailed explanation-1: -An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune system does not recognize the substance, and is trying to fight it off. An antigen may be a substance from the environment, such as chemicals, bacteria, viruses, or pollen.

Detailed explanation-2: -Anything that triggers an immune response is called an antigen. An antigen can be a microbe such as a virus, bacteria, toxins, chemicals or other substances that come from outside the body. If the body comes into contact with an antigen for the first time, it will store information about the germ and how to fight it.

Detailed explanation-3: -Antigens are any substances that the immune system can recognize and that can thus stimulate an immune response. If antigens are perceived as dangerous (for example, if they can cause disease), they can stimulate an immune response in the body.

Detailed explanation-4: -(AN-tih-jen) Any substance that causes the body to make an immune response against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body. Body tissues and cells, including cancer cells, also have antigens on them that can cause an immune response.

Detailed explanation-5: -Upon entering the body, an antigen triggers the adaptive immune system that comprises specialized immune cells, such as B and T lymphocytes (B cells and T cells). There are two types of adaptive immune responses: antibody-mediated and cell-mediated immune responses.