GCE Biology B H022/01: Foundations of biology Advanced Subsidiary GCE Mark Scheme for November 2020

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GCE Biology B H022/01: Foundations of biology Advanced Subsidiary GCE Mark Scheme for November 2020 Oxford Cambridge and RSA Examinations GCE Biology B H022/01: Foundations of biology Advanced Su... bsidiary GCE Mark Scheme for November 2020Oxford Cambridge and RSA Examinations OCR (Oxford Cambridge and RSA) is a leading UK awarding body, providing a wide range of qualifications to meet the needs of candidates of all ages and abilities. OCR qualifications include AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals, Functional Skills, Key Skills, Entry Level qualifications, NVQs and vocational qualifications in areas such as IT, business, languages, teaching/training, administration and secretarial skills. It is also responsible for developing new specifications to meet national requirements and the needs of students and teachers. OCR is a not-for-profit organisation; any surplus made is invested back into the establishment to help towards the development of qualifications and support, which keep pace with the changing needs of today’s society. This mark scheme is published as an aid to teachers and students, to indicate the requirements of the examination. It shows the basis on which marks were awarded by examiners. It does not indicate the details of the discussions which took place at an examiners’ meeting before marking commenced. All examiners are instructed that alternative correct answers and unexpected approaches in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills demonstrated. Mark schemes should be read in conjunction with the published question papers and the report on the examination. © OCR 2020H022/01 Mark Scheme November 2020 4 Annotations Annotation Meaning DO NOT ALLOW Answers which are not worthy of credit IGNORE Statements which are irrelevant ALLOW Answers that can be accepted ( ) Words which are not essential to gain credit Underlined words must be present in answer to score a mark ECF Error carried forward AW Alternative wording ORA Or reverse argumentH022/01 Mark Scheme November 2020 4 Annotation Meaning correct response incorrect response benefit of the doubt benefit of the doubt not given error carried forward information omitted ignore Blank page Marking point partially met Underline (for ambiguous / contradictory wording) contradictionH022/01 Mark Scheme November 2020 5 Subject-specific Marking Instructions INTRODUCTION Your first task as an Examiner is to become thoroughly familiar with the material on which the examination depends. This material includes: • the specification, especially the assessment objectives • the question paper • the mark scheme. You should ensure that you have copies of these materials. You should ensure also that you are familiar with the administrative procedures related to the marking process. These are set out in the OCR booklet Instructions for Examiners. If you are examining for the first time, please read carefully Appendix 5 Introduction to Script Marking: Notes for New Examiners. Please ask for help or guidance whenever you need it. Your first point of contact is your Team Leader.H022/01 Mark Scheme November 2020 8 SECTION A Question Answer Marks AO element Guidance 1 C 1 AO1.1 2 B 1 AO1.2 3 B 1 AO2.8 4 C 1 AO2.8 5 B 1 AO1.2 6 A 1 AO1.1 7 C 1 AO1.1 8 B 1 AO1.1 9 D 1 AO2.5 10 A 1 AO2.8 11 D 1 AO2.5 12 A 1 AO1.2 13 C 1 AO1.2 14 A 1 AO2.1 15 B 1 AO2.4 16 B 1 AO1.1 17 C 1 AO1.1 18 D 1 AO2.1 19 B 1 AO2.1 20 A 1 AO1.1 Total 20H022/01 Mark Scheme November 2020 7 Question Answer Marks AO element Guidance 21 (a) idea that mass lost may not be just water  some water used by plants e.g. for photosynthesis  2 AO3.1 IGNORE references to the accuracy of the balance IGNORE references to water lost to atmosphere (b) (i) number / surface area , of leaves on cutting  (as) increase in surface area would increase , transpiration / number of stomata  OR (thick) waxy cuticle (on leaf surface)  waterproofs the leaf / prevents water loss  OR number / size , of stomata  affects , diffusion / evaporation , (of water) from mesophyll cells  2 max AO2.7 explanation must be linked to factor IGNORE surface area : volume ALLOW ORA for decrease (b) (ii) potometer 4 max AO3.4 ALLOW ora advantages and disadvantages for method in Fig.21.1 measures water uptake  times how long it takes for air bubble to travel fixed distance  advantages transpiration measurements taken over shorter time scale  ALLOW e.g. measure distance travelled by air bubble in fixed time e.g. calculates the rate of movement of the air bubble disadvantages more difficult to set up  needs to be checked regularly / cannot be left for a long time  ALLOW e.g. difficult to ensure no air bubblesH022/01 Mark Scheme November 2020 10 Question Answer Marks AO element Guidance (c) (i) plants could have lost mass due to leaf loss  AVP  1 max AO3.1 IGNORE ref to human error e.g. evapotranspiration e.g. stomata may have closed in secondary data set e.g. different plant species used (ii) 56.5 (%)   2 AO2.8 If answer incorrect ALLOW 1 mark for incorrect sig. figs e.g. 56.52 or 57 (%) OR for (0.36-0.23) ÷ 0.23 (d) (i) stoma Y is open / stoma X is closed  stoma Y guard cells are turgid  lower water potential in guard cell (cytoplasm)  water moves into guard cell by , osmosis / down water potential gradient  3 max AO2.3 ALLOW ora for stoma X (d) (ii) (length) 10 / 11 / 12 / 13  (unit) micrometer or µm  3 AO2.4 If answer incorrect ALLOW 1 mark for incorrect sig. figs. e.g. 12.5 OR correct calculation e.g. 20 mm ÷ 2000 Total 17H022/01 Mark Scheme November 2020 11 SECTION B Question Answer Marks AO element Guidance 22 (a) (i) immune system responds to harmless substance  produces antibodies to , allergen / antigen  inflammatory response triggered 2 max AO1.1 ALLOW harmless antigen ALLOW e.g. causes itching / inflammation (ii) Any two for 1 mark: dust mites  animal hair  mould / fungal spores  (named) food  1 max AO1.1 (b) supporting statements 100% asthmatic sufferers showed sensitivity to allergens by age 24  idea that as age increases there is increasing allergen sensitivity amongst asthmatics  idea of correlation between asthma and allergen sensitivity  negative statements other factors e.g. gender not considered  correlation does not mean causal  4max AO3.4 (c) Chronic condition (asthma is) long-term / slow onset  inflammation is chronic  Acute condition (asthma is) short lasting / sudden onset  (asthma) attack , bronchial spasm , is acute  3 max AO1.1 Total 10H022/01 Mark Scheme November 2020 12 Question Answer Marks AO element Guidance 23 (a) small / reduced volume of , left ventricle small / narrow , aorta  small(er) valves on left side  2 max AO2.1 ALLOW named valves (b) (i) suggestion reduced cardiac output OR increased heart rate / tachycardia OR heart attack  reason lack of , oxygen / nutrients , to , heart / cardiac , muscle  2 AO1.2 (b) (ii) shortens diffusion distance  allows organisms to grow larger  moves substances quickly  2 max AO1.1 ALLOW named substances Total 6H022/01 Mark Scheme November 2020 13 Question Answer Marks AO element Guidance 24 (a) 3 AO1.2 One mark per row  ALLOW AW e.g.so fetus does not get damaged when needle inserted   (b) photograph is taken and cut  chromosomes are put in pairs  chromosomes put in order (of size)  2 max AO2.1 ALLOW e.g. produce computerised image ALLOW e.g. chromosomes in image are rearranged into pairs using computer for two marks (c) (i) abnormality seen on ultrasound scan  family history of (named) syndrome caused by chromosomal mutation  first baby has (named) syndrome  reason for needing to know sex of baby  2 max AO2.1 ALLOW e.g. ultrasound scan shows need for further investigation ALLOW (named) e.g. Down’s syndrome ALLOW (named) e.g. Down’s syndrome e.g. family history of genetic disorder affecting males (c) (ii) amniocentesis can be done at 15 weeks  less chance of miscarriage than CVS  less chance of causing fetal deformities than CVS  2 max AO2.1 CVS or chorionic villus sampling only needs to be mentioned once for MP2 and 3 Total 9 Stage Reason ultrasound locates position of , fetus / placenta addition of colchicine stops mitosis addition of a fluorescent stain allows chromosomes to be seenH022/01 Mark Scheme November 2020 14 Question Answer Marks AO element Guidance 25 (a) globular  quaternary  prosthetic  iron ion  complementary  5 AO1.1 ALLOW Fe ion / Fe2+/ Fe3+ DO NOT ALLOW Fe+ (b) (i) Both needed for 1 mark Reaction hydrolysis Bond peptide  1 AO1.1 (b) (ii) All three correct = 2 marks Any two correct = 1 mark H (atom) NH2 COOH   2 AO2.1 Two marks for complete drawing as example Total 8OCR (Oxford Cambridge and RSA Examinations) The Triangle Building Shaftesbury Road Cambridge CB2 8EA OCR Customer Contact Centre Education and Learning Telephone: 01223 553998 Facsimile: 01223 552627 Email: general.qualifications@ocr.org.uk [Show More]

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