Immunity Flashcards
All 4 cards in this deck
What is an antigen?
A molecule on the surface of a pathogen that the immune system recognises as foreign.
What are the steps of the specific immune response?
e.g. a bacterium enters the body for the first time- Antigens on the pathogen are recognised as foreign.
- Lymphocytes produce antibodies specific to that antigen, leading to destruction of the bacterium.
- Memory lymphocytes are also produced.
True or false? One type of antibody can bind to any type of antigen.
False. Each antibody is specific — its shape is complementary to only one type of antigen.
How does the secondary response differ from the primary response when the same pathogen infects again?
Antibodies are produced faster and in much greater amounts, because memory lymphocytes are already present.
The pathogen is destroyed before symptoms appear.