Memory lymphocytes (Edexcel GCSE Biology Combined Science): Revision Notes

Memory lymphocytes

• When a pathogen enters our body the response is slow as there are many B-Lymphocytes that can make the antibody needed to lock on to the antigen.
• Eventually the body will produce enough of the right antigen to overcome infection meanwhile the person shows symptoms.

Production of Memory Lymphocytes:

• During an initial infection, the immune system responds to the specific antigens on the surface of the pathogen.
• Lymphocytes (a type of white blood cell) produce antibodies to fight the infection.
• After the infection is cleared, some of these lymphocytes remain in the body as memory cells.

Role of Memory Lymphocytes in the Secondary Response:

• If the body is exposed to the same pathogen again in the future, the memory lymphocytes are already present.
• The memory lymphocytes can multiply rapidly and produce large numbers of the specific antibodies required to fight the pathogen.

Faster and Stronger Immune Response:

• The secondary immune response is much faster and more effective than the first response.
  • Memory lymphocytes clone themselves and produce antibodies quickly, often eliminating the pathogen before symptoms appear.

Summary:

• Memory lymphocytes are created after the first exposure to a pathogen and remain in the immune system for a long time.
• If the same pathogen enters the body again, these memory cells ensure a faster and stronger immune response, preventing illness in many cases. This is the principle behind immunity and how vaccines work.