Diseases & Immunity - IGCSE Bio - Extended Supplement

Active Immunity

-The immunity resulting from the production of antibodies in the presence of an antigen

- Antigens can be exposed to the body via an infection or a vaccination

-Specific antigen binds to specific receptor

-Antigen - receptor binding activates the lymphocyte to produce antibodies (which are pretty much the same shape on the receptors but "loose" versions

- Antibodies attach onto their respective pathogen antigens

Vaccination

-Harmless pathogen given to the body (with specific antigens on its surface)

- Immune response triggered as lymphocytes produce antibodies

-Memory cells are produced to give long-term immunity

Passive Immunity

-Short term immunity resulting from the introduction of antibodies from another person or animal

-For example : Mother -> Infant

-Memory cells do not get produced in passive immunity

Type 1 Diabetes

- Pancreas cannot make insulin (which is needed to control blood sugar levels)

-The immune system attacks the cells that make insulin

-Therefore, in some diseases like type 1 diabetes, our immune system attacks our own cells: auto immune disease