And the immune cells of our body are capable of identifying these different antigens. And once the immune cells, the white blood cells, identify the antigens, specialized types of B lymphocytes, known as plasma cells can begin producing antibodies which are highly specific proteins that can bind onto these antigens. And once the antibody is bound to that specific antigen for which it was built for, it elicits some type of defensive mechanism. It basically labels that antigen along with the pathogen for destruction by our immune system. And we'll see exactly how that takes place in just a moment. First, let's discuss the structure of our antibody.