Memory cellsremain in the body and antibodies are produced very quickly if the same antigen is encouraged a second time. The memory providesimmunity following a naturalinfection and after vaccination. The response is highly specific to the antigen involved.
Describing the differences between the primary and secondary response
The primary response is relatively slow, with a delay before antibody production, compared to the secondary response that is much faster
The concentration of antibodiesproduced in the secondary response is much higher compared to the primary response
The concentration of antibodies stays higher for much longer in the secondary response compared to the primary response
Explanation of difference
The presence of memory cells able to detect a 'specific antigen' causes antibodies to be produced very quickly and in large numbers if the sameantigen is encouraged a second time - known as immunity
Why do most people suffer from measles only once, but could suffer from flu many times during lives?
Flu virus mutates rapidly giving rise to new strains with different antigens. Because of this, different antibodies are needed and the memory cells produced during the previous bout of flu cannot recognise the new antigens. The body therefore is not immune to the new strain of flu
