Secondary Immune Response Flashcards
What are the disadvantages of the primary immune response? 2
- Slow as not enough B cells to make needed antigens
- Pathogen multiplies so person feels symptoms
What are saved after the primary immune response?
Memory cells
Explain the secondary immune response 6
- If the same pathogen with the same antigen infects the body
- Immune response is faster and stronger
- As memory B cells make plasma cells with complementary antibodies
- Memory T cells make complementary T killer cells
- As the antigen is recognised
- No symptoms felt
Define “vaccine”
Substance containing antigens from a dead/weakened pathogen
What do vaccines do to the immune system?
Stimulates the primary immune response, so immune system produces:
- Antibodies
- Plasma cells
- Memory cells
What occurs if the body is infected post vaccine? 2
- Undergoes secondary immune response
- No symptoms felt
What do vaccines contain to protect against antigenic variation?
Many different antigens to protect against different strains of pathogens
What is herd immunity?
A higher proportion of the population is immunised so fewer people there to pass on disease
How are vaccines usually administered?
Through an injection
Why are vaccines not taken orally? 3
- Broken down by enzymes
- Too big to be absorbed
- Broken down by stomach acid
Explain antigenic variability and what it means for the immune response 4
- Antigens on the surface of the pathogen change
- As proteins have a different tertiary structure
- Antigen no longer complementary to antibodies in memory cells
- If infected again body must undergo primary response
Why is antigenic variability a problem for vaccines?
Some pathogens have many strains but vaccines can only work on some strains
What are the 4 types of immunity?
- Active natural
- Active artificial
- Passive natural
- Passive artificial
What is active immunity?
Immune system makes its own antibodies after being stimulated by a pathogen
What is natural active immunity?
Immunity after catching a disease and undergoing primary response to produce antibodies and memory cells
What is artificial active immunity?
Immunity after a vaccination and undergoing primary response to produce antibodies and memory cells
What is passive immunity?
Antibodies given that are made from another organism
What is natural passive immunity?
Baby becomes immune after being given antibodies from mother
What are the 2 ways babies can receive antibodies from the mother?
- Through placenta
- Breastmilk
What is artificial passive immunity?
Immunity after being injected with antibodies e.g blood transfusion
What are the advantages of active immunity? 2
- Long term
- Make memory cells
What are the disadvantages of active immunity? 2
- Slow due to primary response
- Must be exposed to pathogen
What are the advantages of passive immunity? 2
- Fast
- No exposure to pathogen needed
What are the disadvantages of passive immunity? 3
- Short term
- No memory cells
- Antibodies are foreign so body breaks them down
