An antigen provokes an immune response in the body, but they are excited by pathogens. 5. Later immune responses which are much faster, more prolonged, and more effective are called active immunity responses. 6. This contains dead or weakened viruses injected to initiate active immunity. A vaccine is an injection with dead or weakened viruses to bolster the body’s immunity to the foreign virus. 7. T cells that remain behind after an infection to provide immunological memory are called memory cells. . A bodywide, acute, allergic response that is fairly rare is called anaphylactic shock. 9. What is it called when the body produces antibodies and sensitized T cells that attack and damage its own tissues? An autoimmune disorder is when the body in essence attacks itself. 10. Tissue grafts taken from unrelated persons are called allografts. 11. Small proteins that diffuse to nearby cells and bind to their membrane receptors are called interferons. 2. Antibodies are also referred to as immunoglobulins or IGS and constitute the gamma globulin part of blood proteins and are formed in response to an antigen. 13. Excess tissue fluid that is picked up and returned to the blood stream by vessels is called lymph capillaries. 14. Complement refers to a group of 20 plasma proteins that circulate in the blood at an inactive site that becomes active when it becomes attached to a foreign cell.