unit 5 principles and application of science

Mark Scheme (Results) June 2018 BTEC Level 3 National in Applied Science Unit 5: Principles and Applications of Science II – Biology (31627H1B)

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Unit 5: Principles and Applications of Science II

General marking guidance • All learners must receive the same treatment. Examiners must mark the first

learner in exactly the same way as they mark the last. • Marking grids should be applied positively. Learners must be rewarded for what

they have shown they can do, rather than be penalised for omissions. • Examiners should mark according to the marking grid, not according to their

perception of where the grade boundaries may lie. • All marks on the marking grid should be used appropriately. • All the marks on the marking grid are designed to be awarded. Examiners

should always award full marks if deserved. Examiners should also be prepared to award zero marks, if the learner’s response is not rewardable according to the marking grid.

• Where judgement is required, a marking grid will provide the principles by which marks will be awarded.

• When examiners are in doubt regarding the application of the marking grid to a learner’s response, a senior examiner should be consulted.

Specific marking guidance

The marking grids have been designed to assess learner work holistically. Rows in the grids identify the assessment focus/outcome being targeted. When using a marking grid, the ‘best fit’ approach should be used.

● Examiners should first make a holistic judgement on which band most closely matches the learner’s response and place it within that band. Learners will be placed in the band that best describes their answer.

● The mark awarded within the band will be decided based on the quality of the answer, in response to the assessment focus/outcome and will be modified according to how securely all bullet points are displayed at that band.

● Marks will be awarded towards the top or bottom of that band, depending on how they have evidenced each of the descriptor bullet points.

BTEC mark scheme Question Number

Answer Additional Guidance

Mark

1 (a)

D Vesicles

1

1 (b)

exocytosis Accept phonetic spelling Ignore ‘secretion’ ‘bulk transport’

1

1 (c) award one mark for each of the following up to a maximum of 2 marks: (Cilia) {beat/wave/waft/sweep/move} (1) (to move) the mucus {up /out of} airways/into throat/coughed or sneezed out (1) to remove {harmful/ named example} substances (1) accept any other appropriate response

allow stops build-up of mucus ignore cilia trap particles e.g. particles/impurities in air/pathogens/pollen/ dust

2

1 (d)

phospholipid bilayer (1) with proteins embedded (1)

allow hydrophobic tail and hydrophilic head for 1 mark accept suitable named example

2

1(e) award one mark for each of the following up to a maximum of 2 marks: mechanical stability/membrane support/strengthens (1) regulates membrane fluidity/increases rigidity (1) prevents loss of ions/named ions/ electrolytes (1)

ignore ‘to make sex hormones’

2

total 8 marks

Question Number


Mark

2 (a)

award one mark for each of the following up to a maximum of 2 marks: to {remove/absorb} carbon dioxide (1) (because carbon dioxide build up) is toxic / is acidic /can lower (blood) pH/to prevent asphyxiation (1) (carbon dioxide) can alter the breathing rate (1) so oxygen consumption can be calculated (1)

Ignore ‘it is dangerous’

2

2 (b)(i)

A 1

2 (b)(ii)

substitution 12 x {0.4 to 0.6} (1) evaluation 4.8 to 7.2 (1)

4.8 to 7.2 alone gains 2 marks 4.8 to 7.2 to any factor of 10 gains 1 mark ECF

2

2 (c) Sketch shows: more breaths per minute than Figure 1.3 (1) higher tidal volume than figure 1.3 (1) (steeper) slope of trace downwards from left to right (1) Example which would gain 3 marks:

Ignore any vital capacity traces Allow full marks even if line on graph not covering the full two minutes

3

total 8 marks

Question Number


Mark

3 (a)(i)

award one mark for each of the following up to a maximum of 2 marks (muscle/heart/ventricle) beat/contracts/pumps (1) on its own/spontaneously/rhythmically (1) without input/signal from {nerves/brain} (1) (muscle) cells are able to depolarise/generate own electric impulses (1)

ignore ‘involuntary’

2

3 (a)(ii)

{carries/delivers/takes/supplies} blood containing {oxygen/glucose/lipids} (1) to {heart muscle/ventricle wall/myocardium} (1)

2

3 (b)

award one mark for each of the following up to a maximum of 4 marks: less oxygen/ oxygenated blood to heart {walls/tissue/muscle/cells} (1) so {less/no} respiration (1) so {less/no} ATP/energy(1) so {part of heart/heart cells} die/scar tissue (1) so heart cannot {beat/pump/contract} (1)

4

3 (c)(i)

A (P)

1

3 (c)(ii) B (X) 1

3 (c)(iii) stroke volume (1) 70 (ml) heart rate (1) 60/0.8 cardiac output (1) 70 x 75

allow 75 5250 alone or 70 x 75 alone are awarded all 3 marks ECF

3

total 13 marks Question Number


Mark

4 (a)

C = Loop of Henle (1) D = {Distal (convoluted) tubule/DCT} (1)

accept phonetic spelling ignore any refs to ascending/descending allow distant (convoluted) tubule

2

4 (b) award one mark for each of the following up to a maximum of 3 marks (aldosterone) acts on the (distal) {tubules/ collecting duct} (1) which (re)absorbs {salt/sodium/Na+}(1) water (re)absorbed (1) by osmosis/ due to decrease in water potential (1) increasing the blood volume (1)

allow more sodium (ions) back into blood

3

Question number

Indicative content

4 (c) Advantages: • no need for regular hospital attendance (for renal dialysis) • more able to live normal lifestyle/ not attached to a dialysis

machine for 8 hours each visit • eat a normal healthy diet • (overall) more cost effective/ less expensive • can have living donors/donation from relative/ people can

donate one of their two kidneys • prolongs life of recipient • routine/straightforward surgery • stem cells/growing organs

Disadvantages: • availability/shortage of donors • reference to opt in/opt out • not an immediate form of treatment • invasive and requires surgery • risk of anaesthetic • risk of infection (due to surgery)/need for wound care • need for tissue matching • risk of rejection • transplant may fail • need for immunosuppressant drugs • increased susceptibility to infections (due to

immunosuppressants) • ethical considerations

Mark scheme (award up to 6 marks) refer to the guidance on the cover of this document for how to apply levels-based mark schemes*. Level Mark Descriptor 0 No awardable content Level 1 1-2 Demonstrates adequate/isolated knowledge of scientific

facts/concepts with generalised comments made Generic statements may be presented rather than linkages being made so that lines of reasoning are unsupported or partially supported The discussion shows some structure and coherence

Level 2 3-4 Demonstrates good knowledge and understanding by selecting and applying some relevant scientific knowledge facts/concepts to provide the discussion being presented Lines of argument mostly supported through the application of relevant evidence The discussion shows a structure which is mostly clear, coherent and logical (could be bullet points or a table)

Level 3 5-6 Demonstrates comprehensive knowledge and understanding by selecting and applying relevant knowledge of scientific facts/concepts to provide the discussion being presented Line(s) of argument consistently supported throughout by sustained application of relevant evidence The discussion shows a well-developed structure which is clear, coherent and logical (could be bullet points or a table)

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Mark Scheme (Final) June 2018 BTEC Level 3 National in Applied Science Unit 5: Principles and Applications of Science II – Chemistry (31627H1C)

Unit 5: Principles and Applications of Science II – sample marking grid













Question Number


Mark

1a D 109.5o 1

1b A 2-bromobutane 1

1ci

(2) Or

CH2BrCBr(CH3)2 (2) Br on C-1 and C-2 atoms (1) Rest of molecule correct (1)

allow any combination of displayed / shortened structural formulae

2

1cii electrophilic (1)

addition (1)

2

1ciii σ (sigma) π (pi) C 1 1

1

1d Explanation linking any three from:

• Only a single (carbon to carbon) bond in ethane / ethene has a double (carbon to carbon) bond (1)

• (Carbon to carbon bond in ethane is) longer (1)

• (Carbon to carbon bond in ethane is) weaker / easier to break (1)

• (Carbon to carbon bond in ethane needs) less energy to break (1)

• More electrons are shared between the two carbon atoms in ethene (1)

• Stronger attraction (between the

carbon atoms in ethene) (1)

Accept any other appropriate response

Allow only sigma in ethane / sigma and pi in ethene/ C=C in ethene Allow ORA throughout

3

total 10 marks

Question Number


Mark

2a 2Cl- Cl2 +2e- Chemical formulae of chloride (on LHS) and chlorine (on RHS) (1) Balancing of species, electrons and charges (1)

allow 2Cl--2e- Cl2 Ignore state symbols Allow multiples

2

2b Award one mark for each of the following up to a maximum of 4 marks: • Membrane keeps chlorine (gas)

separate from {hydrogen (gas) / sodium hydroxide} (1)

• Chlorine will not be able to react with

{hydrogen / sodium hydroxide} (1)

• Membrane allows {Na+ / positive ions / cations} to pass through (1)

• Membrane does not allow {Cl- /

negative ions / anions} to pass through (1)

• The sodium hydroxide solution is not

contaminated with chloride ions (1)

• This gives sodium hydroxide solution

that is has {higher purity/ fewer impurities} (1)

Allow to keep {gases / products} separate Allow to prevent {gases / products} from reacting Allow sodium ions Allow chloride ions Do not allow keep sodium chloride separate from sodium hydroxide Allow pure / not impure

4

total 6 marks

Question Number


Mark

3a Award one mark for each of the following up to a maximum of 3 marks: • Speeds up a reaction (1)

• Provides an alternative pathway/route

(1)

• (With a) lower activation energy (1)

• (Transition metals) change oxidation

state / gain and lose electrons / have a variable oxidation state (1)

• Returns to original oxidation state at

end of reaction (1)

• Provide a surface for the reaction to

take place on (1)

3

3b • Lone pair of electrons donated /

dative covalent bond (1)

• From water / ligand / oxygen (atom) to vanadium(III) (ion) (1)

2

total 5 marks

Question Number


Mark

4a CnH2n+2 (1) 1

4b C3H8 C2H4 + CH4 (2) or

C2H4 (1) CH4 (1)

allow multiples accept CH3CH2CH3 CH2CH2 + CH4

2

4c Award one mark for each of the following up to a maximum of 2 marks: • (Produces more product in) less time

(1)

• Use of lower temperature / less energy

(1)

• Conserves fossil fuels / energy (1)

• Does not react with ethene to form

undesired product / no unwanted side reactions (1)

• Produces higher yields of alkanes (1)

• Can reuse the catalyst (1)

• Only requires small amounts of catalyst

(1)

Any other valid point.

ORA for steam throughout

2

total 5 marks

Question Number


Mark

5a (the enthalpy change) when 1 mole (of a substance) {is combusted / burnt} (1) completely {in oxygen} (1)

Allow element / compound Allow “excess” Ignore reference to standard conditions / conditions

2

5bi (298-273 =) 25 (1)

Accept any answer that would round to 25

1

5bii award 5 marks for -127.3 seen alone calculation for 4 mols of C / 4∆H(carbon): 4 x -393.7 (= - 1574.8) (1) calculation for 5 mols of H2 / 5∆H(hydrogen): 5 x - 285.8 (= - 1429) (1) Summation of values: 4∆H(carbon) + 5∆H(hydrogen) (= -3003.8) (1) Difference between values 4∆H(carbon) + 5∆H(hydrogen) - ∆H(butane) (= -1574.8 –1429 +2876.5) (1) Evaluation: -127.3 correct answer (1)

Ignore sign Ignore sign ECF ECF Accept any value between -126.8 to -127.5 ECF

5

Question number

Indicative content

5c Reaction 1 • exothermic • energy is released to surroundings from system / energy

lost as heat / temperature of surroundings will rise • products have less energy than reactants / lower energy

(level) than reactants • (overall) negative enthalpy change / ΔH = -ve • more energy is released when forming bonds than used

when breaking bonds • activation energy is less for reaction 1 than for reaction 2 • reaction 1 would be expected to be faster • net output energy of reaction provides activation energy

to continue reaction

Reaction 2 • endothermic • energy is absorbed by the system from the surroundings

/ heat transferred from the surroundings / temperature of surroundings will fall

• products have more energy than reactants / higher energy (level) than reactants

• (overall) positive enthalpy change / ΔH = +ve • less energy is released when forming bonds than used

when breaking bonds • activation energy is greater for reaction 2 than for

reaction 1 • reaction 2 would be expected to be slower • net input of energy required to provide activation energy

to continue reaction

6

Mark scheme (award up to 6 marks) refer to the guidance on the cover of this document for how to apply levels-based mark schemes*.

Level Mark Descriptor 0 No awardable content Level 1

1-2 • Adequate interpretation, analysis and/or evaluation of the scientific information with generalised comments being made

• Generic statements may be presented rather than linkages being made so that lines of reasoning are unsupported or partially supported

• The explanation shows some structure and coherence

Level 2

3-4 • Good analysis, interpretation and/or evaluation of the scientific information

• Lines of argument mostly supported through the application of relevant evidence

• The explanation shows a structure which is mostly clear, coherent and logical

Level 3

5-6 • Comprehensive analysis, interpretation and/or evaluation of all pieces of scientific information

• Line(s) of argument consistently supported throughout by sustained application of relevant evidence

• The explanation shows a well-developed structure which is clear, coherent and logical

For more information on Edexcel qualifications, please visit our website www.edexcel.com

Pearson Education Limited. Registered company number 872828 with its registered office at Edinburgh Gate, Harlow, Essex CM20 2JE

Mark Scheme (Results) June 2018 BTEC Level 3 National in Applied Science Unit 5: Principles and Applications of Science II – Physics (31627H1P)

Unit 5: Principles and Applications of Science II













Question Number

Answer Additional guidance Mark

1 (a)(i) B (energy transferred to the box) 1 1 (a)(ii) D Nm-2 1 1 (b) 400 (W) accept 4.0 x 102 (W)

reject 400kW/400MW

1

total marks 3 Question Number


2 (a) B (velocity: higher, Pressure: lower)

1

2 (b)(i) Award one mark for an identification and one mark for a linked expansion up to a maximum of two marks:

(when cold, the oil) will not {flow /move} through the engine {easily /fast/freely} (1) OR the oil is thicker AND (so) the oil will not reach all parts of the engine (1)

ignore oil is more viscous/oil won’t be a good lubricant allow harder for the oil to spread

2

2 (b)(ii) Award one mark for an identification and one mark for a linked expansion up to a maximum of two marks:

(when at a high temperature, the oil) will not coat the moving parts well/oil is {thinner/less dense} (1) (as the oil is thin so will make) engine wear greater/more friction (1) OR the oil will flow {faster/freely/easily/quicker} (1) (so) will not stay in contact with moving parts long enough /more friction/not removing heat fast enough (1)

ignore ‘as the oil gets hotter it gets less viscous’ as it is in the stem allow more slippery/runnier

2

total marks 5

Question Number


3 (a)(i)

substitution (1) 497 000 = m x 4 200 x (100-20) rearrangement (1) m = 497 000 4 200 x 80 evaluation (1) 1.479(kg)

Allow substitution and rearrangement in either order. 497 000 = m x 4 200 x (80) m = energy supplied shc x temp diff allow 1.48/1.47 do not allow 1.5 without any working if no other mark scored award one mark for calculation of temperature change 80 seen if reverse calculation seen e.g. 1.5 x 4200 x 80 = 504 000 award up to 2 marks for substitution and evaluation.

3

3 (a)(ii)

substitution (1) E = 1.5 x 2.26 x 106 evaluation (1) 3.39 x106 (J)

Allow POT for 1 mark allow 3390000/3400000/ 3.4 x106 allow answers rounding to 3.3 x 106 if 1.48 or 1.47 kg if used

2

3 (b)(i) Any two from three:

there is no net (thermal) heat transfer/input energy is balanced by the output energy (1) energy flows/transfers in (from the heat source) and out of the metal plate (to the surroundings) (1) it reaches a maximum temperature (1)

ignore ‘constant’

2

3 (b)(ii) the amount of thermal energy (added to the metal plate) (1) which gives {a rise/change in temperature of 1K/unit temperature rise/change} (1)

allow heat allow ‘by one degree’

2

total marks 9 Question Number


4 (a)(i) the total energy (of an isolated system) remains constant/is conserved (1) OR energy cannot be {created/made} or {destroyed/lost} (1)

ignore ‘energy conserved’ unless qualified allow can’t be lost, just transferred’

1

4 (a)(ii) (W=) work (done by the system)

ignore energy 1

4 (b)(i) An explanation linking any two from the first three points (the) air is compressed (1) (when the user of the pump pushes down on the pump) the volume decreases (1) (so) air pressure increases (1) AND work is done on the gas (1) (so, the) particles/molecules /air gain/increase kinetic energy (from the moving piston) (1)

ignore comments relating to friction in the pump allow gas for air ignore compression of particles allow kinetic energy transferred to molecules

4

4 (b)(ii) substitution (1) 2.5 x 105 x 3.8 x10-4 = n x 1.38 × 10-23 x 303 rearrangement (1) N = 2.5 x 105 x 3.8 x10-4 1.38 × 10-23 x 303 evaluation (1) 2.27 x 1022 (molecules)

Allow substitution and rearrangement in either order. allow N = 95 1.38 × 10-23 x 303 OR 2.5 x 105 x 3.8 x10-4 4.1(814) x 1021 for 2 marks allow answers rounding to 2.3 x 1022 allow POT error for 2 marks if no other mark scored award 1 mark for correct identification of pV=NkT

3

total marks 9

Question Number


5 (a) C malleability

1

5 (b)

(copper can be) {stretched/pulled/put under tension} without breaking/fracturing/cracking (1)

(therefore it) can be {drawn /formed} into a wire (1)

(because layers of) atoms can slide over each other (1)

ignore comments relating to malleability e.g. hammering/moulding/flexibility

3

5 (c)(i) conversion (1) 10 cm and 10.4 cm to 0.100 m and 0.104 m/ or 0.004 m difference substitution (1) 100 = 0.5 x F x (0.104 – 0.100) rearrangement (1)

F = 100

0.5 x 0.004

evaluation (1) 50,000 (N)

Allow conversion/substitution and rearrangement in any order. allow a POT error if the conversion is incorrect to a maximum of 3 marks allow ½ for 0.5 allow 0.4 for sub and rearrangement mark for 0.004 5 x 104(N) allow a mark for 10.4-10.0 if no other mark scored

4

Question number

Indicative content

5 (c)(ii) O to A in the region from O to A the strain is directly proportional to the stress. because Hooke’s law is being obeyed so the forces between the particles allow the steel to extend and return to its original length. at A the elastic limit is reached, and the line ceases to be a direct proportion. so from A the material starts to be deformed plastically. after this point if the stress is removed the steel will be permanently longer than it was originally. B to C B is called the yield point. the steel yields because the crystals that make up the steel slip against each other. between B and C the wire extends plastically due to slippage of the crystals. the increase in strain is not linear as the slippage is unpredictable as the stress increases the crystals lock against each other. so more force is needed to overcome the crystals locking against each other, which results in more stress needed to produce a strain. between B and C the breaking point is reached. the maximum stress is the ultimate tensile stress of the steel the steel will snap with no further increase in stress until it breaks at C. the stress reduces because a neck forms in the steel. the cross-sectional area of the steel reduces. however, the stress is calculated in terms of the original cross section.

Mark scheme (award up to 6 marks) refer to the guidance on the cover of this document for how to apply levels-based mark schemes*.

Level Mark Descriptor

0 No awardable content

Level 1

1-2 Demonstrates adequate knowledge of scientific facts/concepts with generalised comments made. Generic statements may be presented rather than linkages being made so that lines of reasoning are unsupported or partially supported. The explanation shows some structure and coherence.

Level 2

3-4 Demonstrates good knowledge and understanding by selecting and applying some relevant scientific knowledge facts/concepts to provide the discussion being presented. Lines of argument mostly supported through the application of relevant evidence. The explanation shows a structure which is mostly clear, coherent and logical.

Level 3

5-6 Demonstrates comprehensive knowledge and understanding by selecting and applying relevant knowledge of scientific facts/concepts to provide the discussion being presented. Line(s) of argument consistently supported throughout by sustained application of relevant evidence. The explanation shows a well-developed structure which is clear, coherent and logical.

For more information on Edexcel qualifications, please visit our website www.edexcel.com Pearson Education Limited. Registered company number 872828 with its registered office at Edinburgh Gate, Harlow, Essex CM20 2JE

unit 5 principles and application of science

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