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A Level Biology B (Advancing Biology)H422/02 Scientific literacy in biology 2022
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A Level Biology B (Advancing Biology)H422/02 Scientific literacy in biology 2022
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Oxford Cambridge and RSAFriday 15 October 2021 – Morning
A Level Biology B (Advancing Biology)
H422/02 Scientific literacy in biology
Time allowed: 2 hours 15 minutes
You must have:
* 8 9 5 9 1 5 3 9 5 8 *
• a clean copy of the Advance Notice Article (inside
this document)
You can use:
• a ruler (cm/mm)
• a scientific or graphical calculator
* H 4 2 2 0 2 *
Please write clearly in black ink. Do not write in the barcodes.
Centre number Candidate number
First name(s)
Last name
INSTRUCTIONS
• Use black ink. You can use an HB pencil, but only for graphs and diagrams.
• Write your answer to each question in the space provided. If you need extra space use
the lined pages at the end of this booklet. The question numbers must be clearly shown.
• Answer all the questions.
• Where appropriate, your answer should be supported with working. Marks might be
given for using a correct method, even if your answer is wrong.
INFORMATION
• The total mark for this paper is 100.
• The marks for each question are shown in brackets [ ].
• Quality of extended response will be assessed in questions marked with an asterisk (*).
• This document has 28 pages.
ADVICE
• Read each question carefully before you start your answer.
© OCR 2021 [601/4720/9] OCR is an exempt Charity
DC (CJ/FC) 300220/3 Turn over
, 2
Answer all the questions.
1 This question is based on the Advance Notice article ‘Do Pathogens Gain Virulence as Hosts
Become More Resistant?’ on the Insert.
(a) The myxoma virus (MYXV) is a pathogen that causes myxomatosis in its hosts.
(i) Describe how a virus replicates.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [2]
(ii) Explain why myxomatosis could not be described as endemic in Australia before 1950.
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [1]
(iii) Explain why the myxomatosis outbreak in the 1950s could be described as an epidemic.
...........................................................................................................................................
...................................................................................................................................... [1]
(b) HIV is a retrovirus but MYXV is not.
Use this information and your knowledge to complete the following table by placing a tick (✓)
if the feature is found in HIV or MYXV.
Feature HIV MYXV
Genetic material is RNA
Virus particle contains reverse transcriptase
Virus has a protein capsid
[3]
© OCR 2021
, 3
(c) The graph shows how the virulence of MYXV changed over the period from 1950 to 1990.
100
75
Virulence
(% of victims killed) 50
25
0
1950 1960 1970 1980 1990
Describe how the virulence of MYXV strains varied during the period 1950 to 1990.
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
.............................................................................................................................................. [2]
(d) The article describes the interactions between pathogen virulence and host resistance to
infection.
(i) Explain how immunological and genetic factors would allow a population of wild rabbits
to become more resistant to infection by MYXV.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...................................................................................................................................... [2]
© OCR 2021 Turn over
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