GCSE COMBINED SCIENCE: SYNERGY 8465/1F Foundation Tier Paper 1 Life and Environmental Sciences Mark scheme June 2020

01.4 2,8 1 AO2 4.1.2.5 01.5 18 percentage = 1 000 000 × 100 1 AO2 4.4.1.1 01.6 visible light 1 AO1 4.3.2.1 01.7 any two from: • mutations (of genes / DNA / chromosomes) • (skin) cancer • sunburn / burning / blistering (of skin) • eye damage / irritation / cataracts • (premature) skin ageing allow damages genes / DNA / chromosomes 2 AO1 4.3.2.6 4.1.4.3 4.3.1.2 Total 8 Question 2 Question Answers Extra information Mark AO / Spec. Ref. 02.1 (A) (cell) membrane 1 AO1 (B) nucleus 1 4.1.3.2 (C) cytoplasm 1 02.2 B 1 AO1 4.1.3.2 4.1.3.4 4.4.3.1 02.3 40 1 AO2 4.1.3.1 0.25 RPA 3 (×) 160 do not accept if unit given 1 02.4 chloroplast(s) allow chlorophyll 1 AO2 4.1.3.2 4.2.2.5 02.5 cell wall 1 AO1 4.1.3.2 permanent vacuole 1 Total 9 Question 3 Question Answers Extra information Mark AO / Spec. Ref. 03.1 a disease caused by a pathogen 1 AO1 4.3.3.1 03.2 additional line from a box on the left negates the mark for that box 3 AO1 4.3.3.3 03.3 pesticide 1 AO1 4.4.4.6 03.4 3 1 AO2 4.1.3.5 03.5 genes from one organism being transferred to another organism 1 AO1 4.4.4.6 03.6 decreases the use of chemicals to kill mosquitos 1 AO3 4.4.4.6 Total 8 Question 4 Question Answers Extra information Mark AO / Spec. Ref. 04.1 differentiation 1 AO1 4.1.3.6 04.2 additional line from a box on the left negates the mark for that box 3 AO1 4.2.1.4 4.3.3.4 04.3 engulfing pathogens 1 AO1 4.2.1.4 4.3.3.4 04.4 heterozygous 1 AO2 4.4.3.3 04.5 the observable characteristics of an organism 1 AO1 4.4.3.4 04.6 mark with 04.7 and 04.8 allow 1 mark for 1 genotype correct 2 AO2 4.4.3.3 04.7 any rr circled 1 AO2 mark with 4.4.3.3 04.6 and 04.8 04.8 percentage must match answer if no answer in question 04.6 1 AO3 mark with given to question 04.6 and 04.7 allow 25% 4.4.3.3 04.6 and 04.7 04.9 any one from: • to assess / test toxicity • to assess / test efficacy allow to assess / test / see side effects allow reference to safety / harmful / dangerous allow to assess / test / see if the drug works 1 AO1 4.3.3.7 Total 12 Question 5 Question Answers Extra information Mark AO / Spec. Ref. 05.1 must be in this order AO2 diffusion 1 4.1.3.3 active transport 1 05.2 (sodium ion) concentration is higher outside (the cell) allow (sodium ion) concentration is lower inside the cell allow there are more (sodium ions) outside (the cell) allow there are fewer / less (sodium ions) inside (the cell) allow (sodium ions) move from high concentration to low concentration ignore diffusion unqualified 1 AO2 4.1.3.3 05.3 30 allow 30 × or × 30 or 30 times 1 AO2 4.1.3.3 05.4 respiration ignore aerobic / anaerobic 1 AO1 4.2.1.1 05.5 active transport 1 AO1 4.1.3.3 05.6 any two from: • temperature • surface area (of membrane) • concentration (gradient) 2 AO1 4.1.3.3 Question Answers Mark AO/ Spec. Ref 05.7 Level 3: The method would lead to the production of a valid outcome. All key steps are identified and logically sequenced. 5‒6 AO1 4.1.3.3 RPA 4 Level 2: The method would not necessarily lead to a valid outcome. Most steps are identified, but the plan is not fully logically sequenced. 3‒4 Level 1: The method would not lead to a valid outcome. Some relevant steps are identified, but links are not made clear. 1‒2 No relevant content 0 Indicative content • at least 5 concentrations • remove peel • cut pieces of potato • to same mass / size • measure / record initial mass of potato pieces • leave in solutions • for known time (at least 15 minutes if given) • dry pieces • measure / record final mass of potato pieces • calculate change in mass • calculate percentage change in mass • control surface area / size / shape / length • control temperature • control type of potato • repeat and calculate a mean (for each concentration) Total 14 Question 6 Question Answers Extra information Mark AO / Spec. Ref. 06.1 additional line from a box on the left negates the mark for that box 3 AO1 4.1.4.3 06.2 do not accept more than one tick per row 1 1 1 AO1 4.1.4.3 RPA6 06.3 0.5 °C 1 AO3 4.1.4.3 RPA6 06.4 any one from: • 26(.0 °C to) 69(.0 °C) • 69(.0 °C to) 26(.0 °C) ignore 43(.0 °C) 1 AO2 4.1.4.3 RPA6 06.5 3 bars correctly plotted allow a tolerance of +/- 1 of a 2 small square allow any width, bars touching or not allow 1 mark for 2 bars correctly plotted 2 AO2 4.1.4.3 RPA6 3 bars correctly labelled 1 06.6 any one from: • matt black is the best emitter / radiator • shiny silver is the worst emitter / radiator allow black is a good emitter / radiator 1 AO3 4.1.4.3 RPA6 allow silver is a poor emitter / radiator allow an answer in terms of highest / lowest temperature allow matt white and shiny black are (almost) the same at emitting / radiating ignore any reference to absorption / reflection 06.7 v = f × λ 1 AO1 4.1.4.2 06.8 =f × 500 1 AO2 1 AO2 f = 500 f =600 000 1 AO2 hertz / Hz 1 AO1 4.1.4.2 Total 17 Question 7 Question Answers Extra information Mark AO / Spec. Ref. 07.1 prokaryotic cells 1 AO2 4.1.3.2 07.2 13 500 − 9 000 9 000 × 100 allow 4500 9 000 × 100 for 1 mark if no other mark awarded allow 13 500 − 9 000 9 000 = 0.5 for 1 mark 1 AO2 4.3.3.6 50 (%) 1 07.3 any two from: 2 AO2 4.3.3.6 • number of (antibiotic) resistant infections is increasing allow (current) antibiotics don’t always work allow (more) bacteria have become antibiotic resistant • existing tests to find which antibiotic to use are slow allow existing tests to find which antibiotic to use take over 30 minutes • to find new antibiotic(s) allow new antibiotics are needed • (too many) antibiotics are being given for viral infections allow idea of reducing inappropriate use ignore reducing number of people taking antibiotics unqualified • doctors can start effective treatment sooner • (antibiotic) resistant infections cause deaths or burden on doctors / NHS 07.4 antibiotic resistant bacteria are 1 AO2 less likely to evolve 4.3.3.6 4.4.4.3 fewer bacteria will be exposed 1 to antibiotics 07.5 dead / inactive E. coli allow parts of E. coli allow E. coli antigens ignore dead / inactive bacteria / pathogen(s) unqualified ignore italics ignore capitalisation 1 AO2 4.3.3.5 Total 8 Question 8 Question Answers Extra information Mark AO / Spec. Ref. 08.1 any two from: (in a solid) • regular arrangement / pattern (of particles / spaces) • particles are packed close(r) together • particles in a fixed position allow converse allow each particle touches nearest neighbour allow particles are moving less in a solid 2 AO1 4.1.1.1 08.2 a mixture is formed allow a solution is formed 1 AO2 4.1.1.5 (which) has a lower melting point allow (which) has a lower freezing point 1 alternative approach: (mixture) has a lower melting point (1) allow (mixture) has a lower freezing point (so) temperature of surroundings / air / road is not cold enough to keep mixture / ice frozen (1) 08.3 line of best fit ignore extrapolation 1 AO2 view with 4.1.1.5 Figure 10 and mark with 08.4 08.4 view with Figure 10 and mark with 08.3 answer consistent with their line allow ecf from 08.3 if no line drawn allow value between 1.0 and 1.5 (kg) 1 AO3 4.1.1.5 08.5 any two from: • more ice is melted (by 1 kg of grit) at higher temperatures allow converse 2 AO2 4.1.1.5 • increasingly more ice is melted at higher temperatures or gradient increases allow the relationship is not linear / proportional at higher temperatures • use of pairs of values that show more ice is melted at allow a tolerance of +/- ½ a small square higher temperatures 08.6 any one from: • road temperature not air temperature • actual temperature (rather than prediction) • specific to a small area • avoids wasting grit • fewer accidents allow weather forecasts are (often) inaccurate allow reference to cost of grit allow reference to safety 1 AO3 4.1.1.5 Total 9 Question 9 Question Answers Extra information Mark AO / Spec. Ref. 09.1 (fat) mix sample with ethanol and add (distilled) water result must correspond with test 1 AO1 4.2.1.5 RPA7 milky / white / cloudy (if fat is present) 1 or rub food on paper (and allow to dry) (1) greasy mark (if fat is present) (1) allow apply Sudan Red / III / Black stain to food (1) red / black (if lipid is present) (1) (protein) mix sample with Biuret (reagent) allow mix sample with Biuret A and Biuret B 1 allow mix sample with potassium / sodium hydroxide solution and copper sulphate solution mauve / purple / lilac / pink-purple (if protein is present) 1 09.2 in either order AO1 fatty acid(s) 1 4.2.1.5 glycerol 1 09.3 E = 40 × 1250 1 AO2 (= 50 000 (MJ/hour)) 4.4.1.5 4.2.1.5 E = 50 000 × 8760 1 E = (MJ) or 4.38 × 108 (MJ) 1 Question Answers Mark AO/ Spec. Ref 09.4 Level 3: A judgement, strongly linked and logically supported by a 5–6 AO3 sufficient range of correct reasons, is given. Level 2: Some logically linked reasons are given. There may 3–4 AO2 also be a simple judgement. Level 1: Relevant points are made. They are not logically linked. 1–2 AO2 No relevant content 0 4.2.1.5 Indicative content 4.4.1.5 4.4.2.7 4.4.1.2 • fats and coal are stores of energy 4.4.1.6 4.4.1.4 • fatbergs are (partially) renewable • coal is a non-renewable energy source • burning / using fatbergs is using a waste product • prevents sewers from being blocked • costs involved with removing blockages • more useful than sending fatbergs to landfill • if less fats are passed into drains then this will cause a supply issue to the (fatberg) power station • both fuels release carbon dioxide when burnt • fatberg power station might be carbon neutral • (if carbon neutral) global warming may be less • named consequence of global warming • coal releases other pollutants when burnt • such as sulfur dioxide • which can cause respiratory problems and acid rain • other items in fatbergs could cause pollution issues if burnt, or would need to be separated • which would be a cost issue • both fuels may release particulates when burnt • which can damage lungs Total 15