Collective narcissism In graph theory , a clique graph of an undirected graph G is another graph K ( G ) that represents the structure of cliques in G . Clique graphs were discussed at least as early as 1968, [1] and a characterization of clique graphs was given in 1971. [2] Clique Clique (graph theory) What up G? Immunoglobulin G Immunoglobulin G ( IgG ) is a type of antibody . Representing approximately 75% of serum antibodies in humans, IgG is the most common type of antibody found in blood circulation . [1] IgG molecules are created and released by plasma B cells . Each IgG has two antigen binding sites. Immunoglobulin M ( IgM ) is one of several isotypes of antibody (also known as immunoglobulin) that are produced by vertebrates . IgM is the largest antibody, and it is the first antibody to appear in the response to initial exposure to an antigen . [1] [2] In the case of humans and other mammals that have been studied, the spleen