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6 mark questions and answers biology triple
79 minutes
79 marks
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Q1. A student is given a tube containing a liquid nutrient medium. The medium contains one type of bacterium.
(a) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
The student is told to grow some of the bacteria on agar jelly in a Petri dish.
Describe how the student should prepare an uncontaminated culture of the bacterium in the Petri dish.
You should explain the reasons for each of the steps you describe.
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(b) After the culture had been prepared, the student added one drop of each of five disinfectants, A, B, C, D and E, onto the culture.
The diagram shows the appearance of the Petri dish 3 days later.
(i) There are areas on the agar jelly where no bacteria are growing.
Why?
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(ii) The student concluded that disinfectant D would be the best for using around the home.
Give one reason why the student might be correct.
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Give one reason why the student might not be correct.
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(Total 9 marks)
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Q2. In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
The diagram shows part of the carbon cycle.
Describe how living things are involved in the constant cycling of carbon.
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Q3. In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
The diagram below shows a food web for some of the organisms that live on moorland.
Only a small percentage of the Sun’s energy captured by the heather is eventually incorporated into the body tissues of the fox.
Explain, as fully as you can, what happens to the rest of the energy captured by the heather.
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Q4. Humans damage the environment in many ways, including deforestation.
© Kazuyoshi Nomachi/Corbis
In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
The diagram shows an area where the forest is being cleared.
Describe the reasons why deforestation is taking place and the effects that deforestation has on the environment.
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Q5. Sometimes babies are born with extra fingers or toes as shown in the photograph.
This condition is called polydactyly.
©CNRI / SCIENCE PHOTO LIBRARY
The diagram shows the inheritance of polydactyly in a family.
(a) Polydactyly is caused by a dominant allele, D. The recessive allele of the gene is represented by d.
Use one genetic diagram to show the inheritance of the polydactyly gene by R and S.
(4)
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(b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
Embryos can be screened for genetic disorders.
Many people would favour the use of embryo screening for cystic fibrosis but not for polydactyly.
Compare the issues involved in the use of embryo screening for cystic fibrosis and for polydactyly. You should use your knowledge and understanding of the process and the two conditions.
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(Total 10 marks)
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Q6. During evolution, many groups of animals have become extinct (died out).
(a) The graph shows how the number of animal groups has changed over time.
Harold L Levin, The Earth Through Time,© 2005,
Reprinted with permission of John Wiley & Sons, Inc.
How has the number of animal groups changed between 200 million years ago and the present day?
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........................................................................................................................ (1)
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(b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
Describe the different causes of the extinction of organisms. Your description should include possible reasons for the mass extinctions shown on the graph.
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(Total 7 marks)
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Q7. Some students investigated the distribution of some of the plants growing in and around a shallow stream. They sampled along a transect line.
The diagram shows their results.
(a) (i) Name the one species that grew only in the driest conditions.
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(ii) Only one species grew in the marsh, the swamp and in the aquatic zones.
Which species?
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(iii) Duckweed grows floating in water. What evidence is there for this in the students’ results?
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(b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
Describe how you would use a -metre × -metre quadrat frame and a 30-metre tape measure to obtain data similar to the data shown in the diagram.
You should include details of how you would make sure that you would obtain valid results.
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(Total 9 marks)
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Q8. (a) The graph shows the effect of pH on the activities of three enzymes, X, Y and Z. These enzymes help to digest food in the human digestive system. Each enzyme is produced by a different part of the digestive system.
pH
(i) What is the optimum (best) pH for the action of enzyme Z?
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(ii) The stomach makes a substance that gives the correct pH for enzyme action in the human stomach.
Name this substance. .................................................................................................. (1)
(iii) Which enzyme, X, Y or Z, will work best in the human stomach?
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(b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
Different parts of the human digestive system help to break down molecules of fat so that they can be absorbed into the body.
Describe how.
To gain full marks you should refer to:
• the enzyme and where the enzyme is produced
• the products of digestion
• any other chemicals involved.
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(Total 9 marks)
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Q9. The photograph shows a zorse.
By Kumana @ Wild Equines [CC-BY-2.0], via Wikimedia Commons
A zorse is a cross between a male zebra and a female horse. The zorse has characteristics of both parents.
(a) The zorse was produced by sexual reproduction.
(i) What is sexual reproduction?
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(ii) The zorse has characteristics of a zebra and a horse.
Why?
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(b) Zorses are not able to breed. Scientists could produce more zorses from this zorse by adult cell cloning.
The diagram shows how the scientists might clone a zorse.
In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
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Use information from the diagram and your own knowledge to describe how adult cell cloning could be used to clone a zorse.
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(6) (Total 9 marks)
Q10. In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
Plants and animals have become adapted in many different ways to reduce the risk of being eaten by predators.
Describe these adaptations.
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Give examples of animals and plants adapted in the ways you describe.
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(Total 6 marks)
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M1. (a) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also refer to the information in the Marking guidance, and apply a ‘best-fit’ approach to the marking.
0 marks No relevant content.
Level 1 (1-2 marks) There is a brief description of at least one of the stages (pre-inoculation, inoculation, post-inoculation).
Level 2 (3-4 marks) There is a simple description of at least two stages and an explanation of at least one of them.
Level 3 (5-6 marks) There is a clear description of all three stages and an explanation of at least two of them.
Examples of Biology points made in the response:
Pre-inoculation
• Petri dish and agar sterilised before use
• to kill unwanted bacteria
• inoculating loop passed through flame / sterile swab
• to sterilise / kill (other) bacteria
Inoculation
• loop/swab used to spread/streak bacterium onto agar
Allow other correct methods, eg bacterial lawns
• lid of Petri dish opened as little as possible
• to prevent microbes from air entering
Post-inoculation
• sealed with tape
• to prevent microbes from air entering
• incubate
• to allow growth of bacteria 6
(b) (i) bacteria killed / destroyed ignore fights / attacks / stops growth / got rid of
1
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(ii) Might be correct
largest area / space where no bacteria are growing allow most bacteria killed
1
Might not be correct
(need more evidence as) D may be harmful to people / animals / surfaces ignore ref to cost / dangerous or harmful unqualified
1
or may work differently with different bacteria
or disinfectants may be different concentrations
ignore different amounts of disinfectant unless reference to different drop size
or may not last as long
ignore take longer to work allow reference to anomalous result or not repeated
[9]
M2. Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also refer to the information in the Marking guidance.
0 marks No relevant content.
Level 1 (1-2 marks) For at least one process either the organism that carries it out or the carbon compound used or the carbon compound produced is described or for at least one organism either the carbon compound it uses or the carbon compound it produces is described or at least one process is named
Level 2 (3-4 marks) For some processes (at least one of which is named) either the organisms involved or the carbon compounds used or the carbon compounds produced are described
Level 3 (5-6 marks) For at least one named process an organism and either the carbon compound used for the process or the carbon compound produced by the process are described and for other processes (at least one of which is named) either the organism or the carbon compounds used or the carbon compounds produced are described (as in Level 2)
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Examples of Biology points made in the response:
• (green) plants photosynthesise
• photosynthesis takes in carbon dioxide
• (green) plants use carbon to make carbohydrate / protein / fat / organic compounds / named (e.g. enzymes / cellulose)
• animals eat (green) plants (and other animals)
• (green) plants respire
• animals respire
• respiration releases carbon dioxide
• (green) plants and animals die
• microorganisms decay / decompose / rot / break down / feed on dead organisms
• microorganisms respire [6]
M3. Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response.
No relevant content. 0 marks
There is a brief explanation of at least two ways in which the energy captured by the heather is transferred, which has little clarity and detail. Credit may be awarded either for references to general ways in which organisms transfer energy or to ways in which specific organisms in the food web transfer energy.
Level 1 (1–2 marks)
There is some explanation of a range of the ways in which the energy captured by the heather is transferred. Credit may be awarded either for references to general ways in which organisms transfer energy or to ways in which specific organisms in the food web transfer energy.
Level 2 (3–4 marks)
There is a clear, balanced and detailed explanation of a large variety of ways in which energy captured by the heather is transferred Credit may be awarded either for references to general ways in which organisms transfer energy or to ways in which specific organisms in the food web transfer energy.
Level 3 (5–6 marks)
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examples of biology points made in response
• respiration releases energy (allow this point even if given for named organism) NB: to gain full marks, candidates must gain this mark.
• some energy lost in animals / named animal’s waste materials
• some energy used in maintenance / repair (allow this point if given for named organism)
• some energy used for movement (allow this point if given for named animal)
• energy lost as heat to surroundings (allow this point if given for named organism)
• some organisms die (rather than being eaten) (allow this point if given for named organism)
• reference to detritivores / microbes [6]
M4. Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response.
No relevant content. 0 marks
There is a brief description of at least one reason for deforestation or at least one effect of deforestation.
Level 1 (1–2 marks)
There is a scientific description of the reasons for deforestation and an attempt at the effects of deforestation but the account is limited to either direct or indirect effect.
Level 2 (3–4 marks)
There is a clear and detailed scientific description of the reason for deforestation and effects on the environment.
Level 3 (5–6 marks)
examples of biology points made in the response
reasons for deforestation:
• timber
• land for agriculture
• roads and buildings
• land for biofuels
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effects of deforestation:
• reduction in biodiversity
• increase in carbon dioxide content of atmosphere
• global warming
• climate change
• rising sea levels
• changes in migration patterns [6]
M5. (a) (genotype / gametes from P / father) D and d (*) 1
(genotype / gametes from Q / mother) d and d / accept d(*) 1
offspring genotypes correctly derived from correct gametes(*) 1
offspring phenotypes R and S identified 1
(*) eg may be in punnett square allow own upper and lower case symbols or allow any symbol correctly used with key
(b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response.
No relevant content. 0 marks
There is a brief description of the issues involved in screening for at least one condition.
Level 1 (1–2 marks)
There is some description of issues involved in screening for both conditions but there is a lack of both pros and cons for the two conditions.
Level 2 (3–4 marks)
There is a clear, balanced and detailed description of the issues involved in screening for both conditions, giving pros and cons for each condition.
Level 3 (5–6 marks)
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examples of biology points made in the response
For cystic fibrosis
pros:
• reduce number of people with cystic fibrosis (in population)
• reduce health-care costs
• allows decision / emotional argument, eg allows people to make choices about termination
cons:
• possible damage / risk to embryo / fetus / baby
• possible harm / risk to mother
• (may) have to make ethical / moral / religious decisions
for polydactyly:
• cures ‘disfigurement’
• but condition not life threatening
• so risks to foetus / mother unjustified [10]
M6. (a) increased by about 7 times / from 600 to 4300 / by 3700 1
(b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response.
No relevant content 0 marks
There is a brief description of at least two causes of extinction, which has little clarity and detail.
Level 1 (1–2 marks)
There is a description of some causes of extinction, including both small-scale and large-scale events but there is a lack of clarity and detail.
Level 2 (3–4 marks)
There is a clear, balanced and detailed description of at least five causes of extinction, including both small-scale and large-scale events.
Level 3 (5–6 marks)
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examples of biology points made in the response:
• changes to the environment / named changes
• new competitors
• new diseases
• new predators
• volcanic eruptions
• collisions with asteroids [7]
M7. (a) (i) (white) clover 1
(ii) reed sweet-grass allow reed allow grass
1
(iii) (only) found in swamp and aquatic zones or only found in water or doesn’t grow in marsh
ignore wet conditions 1
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(b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also apply a ‘best-fit’ approach to the marking.
0 marks
No relevant content.
Level 1 (1-2 marks) There is a basic description which describes how a quadrat or a metre tape could be used to collect data
Level 2 (3-4 marks) There is a clear description of how a quadrat and a metre tape could be used to collect data along a line
Level 3 (5-6 marks) There is a clear, logical and detailed description of a method that will produce valid, repeatable results across / at intervals along the stream.
examples of procedural points made in the response:
• use of tape measure to produce transect
• placing of quadrats
• transect placed across stream
• score presence of each plant species
• use quadrat at regular intervals along tape
• repeat transect several times (≥ 3)
• along stream
• at random or regular intervals 6
[9]
M8. (a) (i) 8.6
accept value in range 8.5 to 8.7 1
(ii) hydrochloric acid / HCl accept HCL accept hydrogen chloride ignore hcl / etc.
1
(iii) X 1
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(b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also refer to the information in the Marking guidance.
0 marks No relevant content.
Level 1 (1-2 marks) There is a simple description of part of a process or a reference to at least one of: mechanical digestion, lipase, product of enzyme action, bile, site of production or site of digestion
Level 2 (3-4 marks) There is a description of at least one process linking ideas
Level 3 (5-6 marks) There is a clear description of the process including reference to the majority of: mechanical digestion, lipase, bile, where they are produced, products, function of bile and site of digestion / absorption
Examples of biological points made in the response:
• mechanical breakdown in mouth / stomach
• fats →fatty acids and / or glycerol
• by lipase
• (produced by) pancreas
• and small intestine
• fat digestion occurs in small intestine
• bile
• produced by liver
• neutralises acid from stomach
• produces alkaline conditions in intestine
• refs. to increased surface area related to emulsification or chewing
• products are small molecules / water-soluble
• products absorbed by small intestine 6
[9]
M9. (a) (i) fusion / joining / combining of gametes / egg and sperm / sex cells
accept fertilisation allow fusion / joining / combining DNA from two parents ignore meeting / coming together / mixing of gametes etc
1
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(ii) (mixture of) genes / DNA / genetic information / chromosomes ignore nucleus / inherited information but allow second mark if given
1
from both parents / horse and zebra
dependent on sensible attempt at 1st mark
1
(b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should apply a ‘best-fit’ approach to the marking.
0 marks
No relevant content
Level 1 (1-2 marks) There is simple description of the early stages of adult cell cloning. However there is little other detail and the description may be confused or inaccurate.
Level 2 (3-4 marks) There is an almost complete description of the early stages of the process and description of some aspects of the later stages. The description may show some confusion or inaccuracies.
Level 3 (5-6 marks) There is a clear, detailed and accurate description of all the major points of how adult cell cloning is carried out.
Examples of Biology points made in the response could include:
• skin cell from zorse
• (unfertilised) egg cell from horse
• remove nucleus from egg cell
• take nucleus from skin cell
• put into (empty) egg cell
• (then give) electric shock
• (causes) egg cell divides / embryo formed
• (then) place (embryo) in womb / uterus 6
[9]
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M10. Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also apply a 'best-fit' approach to the marking.
0 marks
No relevant content.
Level 1 (1-2 marks) There is at least one example of an adaptation of either an animal or a plant. However it may not be clear how the adaptation helps the organism to avoid being eaten.
Level 2 (3-4 marks) There is a description of an adaptation of at least one animal and at least one plant. It is clear how at least one of these adaptations helps the organism to avoid being eaten.
Level 3 (5-6 marks) There are clear and detailed descriptions of a range of adaptations of named animals and named plants. It is clear how most of these adaptations help the organisms to avoid being eaten.
examples of clear and detailed biology points made in response:
• camouflage – the method of camouflage should be described plus a statement that the predator is less likely to see the prey
• mimicry / warning colouration – the method should be described plus a statement that the predator is likely to confuse the prey with e.g. a poisonous organism
• thorns / prickles / spines / horns – a statement that these are sharp and are likely to hurt a predator
• long limbs / streamlining – a statement that these increase speed and make it more likely that prey will outrun predator
• bad taste / poison – a statement that predator will find this unpleasant and ‘spit out’ prey / not attack same prey again
• large ears / position of eyes – a statement that predators will be detected earlier so the prey can escape sooner
[6]
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E1. (a) The quality of the written communication of many students was pleasing. Many good descriptions of the procedures were seen and students had obviously been involved in practical work involving microorganisms. References to ‘inoculating loops’ (though not necessarily named as such) and ‘pressure cookers’ for sterilising, were seen. However sterilising the surface of agar with a hot inoculating loop would not be an efficient sterilising method. A few students suggested sterilisation of the loop after it had been used to collect the bacteria, in order to ‘kill the bad bacteria’. Some students did not give reasons for the steps they described and so limited their mark to Level 1. Lengthy descriptions of safety precautions such as gloves, goggles and tying the hair back were not required. Common omissions included the tape used for sealing the prepared plate or an instrument for transferring the bacteria. Often the latter was done by being ‘picked up carefully by the fingers’. Some students described practical work they had done, for example with fingerprints or bacteria from doorknobs, but unfortunately they did not match the question which was asked. However, it was possible to gain some marks for practical techniques and explanations appropriate to the question. Some students were unfamiliar with the topic and did no more than repeat the stem of the question.
(b) (i) Many students knew that the bacteria had been killed or destroyed. Answers which described the disinfectant ‘fighting’ or ‘attacking’ the bacteria were insufficient. Stopping the growth of the bacteria was ignored, since bacteria must have been growing in that area before the disinfectant was added.
(ii) Examiners were looking for the idea that the area around disinfectant D was the largest space where no bacteria were growing. Indication that this was only ‘the largest clear area’ was considered to be insufficient without qualification relating to the numbers or growth of bacteria. Answers which said most bacteria were stopped from growing were allowed in this part. The most common suggestion as to why the student might not be correct, was that the disinfectant might be harmful to people or animals or that it might work differently on other bacteria. The idea that the disinfectant was ‘dangerous’ needed qualification as to what the danger might be to gain the mark. The examiners were not surprised at the power of advertising, some students suggesting that the disinfectant might ‘be too strong’ and so kill ‘good bacteria’, too. A number of students gained a mark for pointing out that the investigation needed to be repeated.
E2. There were some good attempts at describing the carbon cycle with students correctly naming carbon compounds required / produced in biological processes. There was some confusion around whether carbon dioxide was entering or leaving plants and animals during photosynthesis and respiration and it was not unusual to read of ‘carbon’ rather than ‘carbon dioxide’ being transferred. A common misconception was to think that carbon dioxide was released by decay rather than being released by the respiration of the microorganisms. The role of microorganisms was generally not well known, many students implying that they ‘eat’ dead or even living plants / animals or were themselves eaten by animals.
There was evidence that many students had made a special effort with the quality of written communication in this question. On the whole those answers which contained considerable biological detail were well-written.
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E7. This was the first of two standard demand questions common to both the Foundation and Higher Tier papers.
(a) Parts (i) and (ii) posed no difficulty to the vast majority of students who were able to select the correct plants from the diagram.
(iii) Descriptions were often imprecise: the duckweed was present in both the aquatic and the swamp regions of the stream (or only in areas covered in water), not just where water was “present”.
(b) A fifth of Foundation Tier students did not even attempt this question. It was evident from what most students wrote that they had little knowledge of the use of a quadrat for sampling along a transect. Many described a method involving random placing of the quadrat in an area, presumably reflecting a practical exercise they had performed but not understanding that such an approach would not generate data as shown in the diagram. Most Foundation Tier students were in this category and thus scored between zero and two marks.
Some better students indicated that the tape measure should be laid out in a straight line and the quadrat placed at intervals along it. Very few students pointed out that this should be done with the tape laid across the stream and that the exercise should be repeated, perhaps at intervals along the stream. It was surprising how few students described how the presence and absence of the different plant species (there were 8 given in the data) should be recorded each time the quadrat was placed: many students merely referred to unspecified “results” being recorded.
E8. This was the third of the three common questions.
(a) A little over half of students were able to read enzyme Z’s optimum pH from the graph as 8.6. However, only a fifth of the students knew that hydrochloric acid was the substance that generated the correct pH for enzyme action in the human stomach, with a little under one-third identifying enzyme X (showing an optimum pH of 1.9 in the graph) as the one that would work best in the stomach.
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(b) In this question, students were required to describe how the human digestive system was able to break down molecules of fat so that they could be absorbed by the body. The quality of written communication was also taken into account in the awarding of marks. Many students found this question very difficult with only a minority displaying a good knowledge of fat digestion. Many knew that lipase was involved, although the term was often confused with ‘lipid’, and that fat was converted into fatty acids. Relatively few knew that the lipase was produced in the pancreas and / or the small intestine (the mouth and stomach were common errors). A fair proportion knew that bile was involved but there was much confusion about where it was made, its storage in the gall bladder being better known. Only a few were able to explain that the bile was alkaline and hence helped to neutralise the acid coming into the small intestine from the stomach (a common error was to suggest that bile entered the stomach to neutralise the acidity); and few knew that the bile emulsified the fat, or were able to describe this process as the production of tiny droplets of fat (the breakdown of fat molecules was a common error here). Some students also explained how initially the food could be broken down mechanically by the teeth and how eventually the products of digestion could be absorbed by the small intestine. Many students were confused about which processes occurred where, about the name of the enzyme (‘amylase’ was a common error) and about the products of digestion (e.g. ‘amino acids’ were sometimes suggested). One major mistake, made by a large proportion of students, was to misinterpret the question and not limit themselves to the remit of fat digestion. Consequently, these students wasted a great deal of time giving details of carbohydrate and protein digestion which were not required and for which no marks were available. The only penalty incurred was that of wasting valuable time which could have been better devoted to gaining marks elsewhere.
E9. (a) (i) The examiners had hoped that students would be well-versed in a definition of ‘sexual reproduction’. Unfortunately, this was not the case and there were only a small number of very good answers which included reference to the fusion of gametes or fertilisation. Instead, answers more often referred to the need for ‘two parents’, ‘sexual intercourse’ or ‘producing a baby’, and no mark was awarded. A significant number of students referred to gametes which ‘met’ or ‘mixed’, rather than ‘fused’, and these ideas were not credited.
(ii) Students fared better in this part, where many described the significance of the ‘genes’ of the two parents resulting in the characteristics of the zorse, and so gained both marks. A common error was simply to rephrase the question and provide no extra information, for example ‘it has the characteristics of the horse and zebra’. It should be noted that acquisition of the second mark, in the mark scheme, was dependent upon a sensible attempt at identifying what was responsible for the characteristics.
(b) Many students were able to use the diagram to help them to describe some of the early stages of adult cell cloning, though the origin of the cells was not always given. Others managed to go on to describe some or all of the later stages and gain more credit. A common error was poor observation of the diagram which showed the nucleus of the skin cell being transferred, thus many answers referred to the whole zorse skin cell being put into the egg cell, rather than just the nucleus. Some confused students described this as fertilisation, while others included sperm. Many students placed embryos into horses but failed to point out the uterus and only a small minority included ideas about electric shock treatment, often at the wrong stage. Students should be reminded that good quality QWC skills will affect the mark they gain for their biological knowledge in these questions and it was apparent that the majority paid scant attention to this. The lack of sentences, capital letters, full stops and correct spellings meant that some students were penalised. Marks were spread across the range from 0 to 6, however very few students reached the higher level.
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E10. A large proportion of students did not read the question carefully enough. These students usually spotted the word ‘adaptations’ in the question and wrote all they knew about adaptations to cold and dry habitats. Thus examiners often read through long accounts, filling all 19 lines and beyond, of the various adaptations of polar bears to life in the Arctic and of cacti to life in the desert (or ‘dessert’). Among this, as if by chance, students often happened to mention camouflage and / or spines. The frequent linking of camouflage in polar bears to its ability to ‘avoid being seen by prey’, gained no credit. Students who were more focussed often gave several different adaptations but lack of sufficient detail or explanation made it impossible to move beyond Level 1. For ‘camouflage’ the detail required was that the animal’s coat colour would match that of the surroundings, so that predators are less likely to see the animal. Students are not expected to know the food chain of animals such as polar bears, so this explanation linked to a polar bear was accepted. Similarly for the ‘spines on cacti’, it was necessary for the student to explain that attempts by a consumer to eat the cactus would hurt the consumer. To move into Level 2, students needed to refer to adaptations in both animals and plants and to give a detailed description of one adaptation. It was very rare for students to give answers at Level 3, which required details of at least two adaptations for both plants and animals along with correct references to how this helps them avoid being eaten . Venus fly-traps figured in many responses. There were many confused accounts of these plants with references to their ‘mouths’ and ‘saliva’. The insects which they catch are not their predators, nor are they ‘eaten’, so no credit could be given. It was evident that students, trying to expand their answers to address the “many different ways” referred to in the question had vague memories of the names of organisms, their adaptations and what might eat them, thus examiners were treated to suggestions such as ‘mountain tigers preying upon penguins’ and plants being ‘camouflaged to blend in with the background’. Students should be aware that ‘bright colours’ or ‘warning colours’ do not in themselves protect the animal or plant from being eaten. It is necessary for the potential consumer to have had some unpleasant experience of the colouration and learned to associate the colour with that experience.
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