A student claims that active immunity and passive immunity both provide long-term protection against infection. Evaluate this claim.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Vaccination programmes rely on stimulating the immune system to produce memory cells. However, some individuals, such as newborns, may receive ready-made antibodies from their mothers either across the placenta or through breast milk.
Model answer (4 marks)
Active immunity, produced by vaccination, generates memory B and T cells that persist for years, giving long‑term protection.
Passive immunity, supplied as maternal IgG or breast‑milk antibodies, is short‑lived; the antibodies are degraded after weeks to months and no memory cells are formed.
The key difference is that active immunity relies on the recipient’s adaptive immune system creating memory cells, whereas passive immunity relies on external antibodies without memory.
Therefore the student’s claim is incorrect – only active immunity provides long‑term protection.
Passive immunity, supplied as maternal IgG or breast‑milk antibodies, is short‑lived; the antibodies are degraded after weeks to months and no memory cells are formed.
The key difference is that active immunity relies on the recipient’s adaptive immune system creating memory cells, whereas passive immunity relies on external antibodies without memory.
Therefore the student’s claim is incorrect – only active immunity provides long‑term protection.
Examiner tips
- State the duration of protection for each type; mention memory cells for active, lack thereof for passive.
- Highlight the mechanism difference (memory cells vs external antibodies).
- Conclude clearly that the claim is false.
- Use UK spelling and correct terminology.
Common mistakes
- Confusing the duration of passive immunity with active immunity.
- Failing to mention memory cells as the distinguishing feature.
- Giving a vague or unsupported judgement.
Mark scheme (4 marks)
- Active immunity does provide long-term protection
- Passive immunity does NOT provide long-term protection
- A valid comparative point distinguishing the mechanism of the two types
- A supported overall judgement on the student's claim
Key terms in this question
active immunity · passive immunity
Related
- All OCR A-Level Biology A (H420) revision notes →
- How to answer a "Evaluate" question →
- Decode the mark scheme abbreviations →
More Communicable diseases & immunity questions
- Explain why a person who has recovered from one strain of influenza virus may st…
- A child receives a vaccination containing a weakened form of a pathogen. Several…
- Explain why a person who has recovered from one strain of influenza virus may st…
- Explain why a person who has recovered from one strain of influenza virus may st…