Question 1
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanAntibodies are:
- lipids with a shape complementary to an antigen
- proteins with a shape complementary to an antigen
- carbohydrates with a shape identical to an antigen
- white blood cells that engulf pathogens
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Answer: B (1)
Question 2
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDescribe how antibodies help to destroy a pathogen.
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- pathogen has antigens / antigens have specific shapes (1)
- antibody has a complementary shape / fits the antigen (1)
- antibody binds to the antigen (1)
- pathogen destroyed directly (1)
- or pathogen marked for destruction by phagocytes (1)
- reject antibodies engulf / eat pathogens; reject antibody described as a cell
- Max 4
Question 3
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDefine active immunity and state two ways in which it can be gained.
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- defence against a pathogen by antibody production in the body (1)
- after an infection by a pathogen (1)
- by vaccination (1)
Question 4
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanOutline the process of vaccination.
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- weakened pathogens or their antigens are put into the body (1)
- antigens stimulate lymphocytes to produce antibodies / an immune response (1)
- memory cells are produced that give long-term immunity (1)
Question 5
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanWhat gives long-term immunity after vaccination?
- Antibodies from the mother
- Memory cells
- Stomach acid
- Mucus
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Answer: B (1)
Question 6
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanExplain how vaccinating a large part of a population helps control the spread of a disease.
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- fewer people can become infected / fewer susceptible hosts (1)
- pathogen is passed on less often / harder to find a new host (1)
- so people who are not vaccinated are less likely to be infected (1)
Question 7
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanA baby is breast-fed. Explain how breast-feeding helps to protect the baby against disease, and why this protection does not last.
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- breast milk contains antibodies from the mother (1)
- antibodies protect the baby against pathogens (1)
- baby's immune system is not fully developed / baby has not made its own antibodies yet (1)
- this is passive immunity (1)
- memory cells are not produced (1)
- so protection is short-term / ends when antibodies are broken down (1)
- Max 5
Question 8
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanCompare active immunity with passive immunity.
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- active: antibodies made by the person's own lymphocytes; passive: from another individual (1)
- active: gained by infection or vaccination; passive: via placenta or breast milk (1)
- active: memory cells produced; passive: not produced (1)
- active: long-term; passive: short-term (1)