Question 1
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanExplain how inflammation helps to destroy pathogens at a site of infection.
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Question 2
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanDescribe how interferon and lysozyme each help to protect the body from infection.
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Question 3
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanExplain why an antibody that binds to the surface of one species of bacterium does not bind to a different species.
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Question 4
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanDescribe the roles of B cells and T cells in the immune response to a pathogen that the body has not met before.
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Question 5
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanA person was given a vaccine on day 0 and a second dose of the same vaccine on day 28. The table shows the concentration of antibody in the blood. (a) Describe the differences between the response to the first dose and the response to the second dose. (3) (b) Explain the differences you have described. (2)
| Day | Antibody concentration / arbitrary units |
|---|---|
| 0 | 0 |
| 7 | 2 |
| 14 | 18 |
| 21 | 30 |
| 28 | 22 |
| 35 | 95 |
| 42 | 150 |
| 49 | 120 |
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Question 6
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanCompare and contrast natural passive immunity with artificial active immunity.
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Question 7
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanA baby is protected from infection by antibodies in colostrum. What type of immunity is this?
- Natural active
- Natural passive
- Artificial active
- Artificial passive
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Question 8
Unit 4 style
A Level only (what this means)
A Level only: only in the full A Level, not the AS Level. AS Level students can skip it. What the labels meanExplain how the way in which HIV evades the immune system supports the theory of an evolutionary race between pathogens and their hosts.