| Term | Description | SeeAlso |
| J Segment | Antibodies are created by the stochastic (random) splicing of three different gene sequences: a V Segment, a J Segment, and a D Segement. In this way, the immune system can create many different antibodies. Note that the joining of the V, J, and D segment is somewhat sloppy, resulting in even more mutations and variations in antibodies. | Antibody, Antigen |
| Jonas Salk | Scientist who created a polio vaccine by culturing the virus on mono-layers of monkey kidney cells, treating the viruses briefly with formaldehyde which reacted with the amine groups of the nucleic acids, attenuating (disabling) the virus. | Virus, Albert Sabin |