(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 1 / 20 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 20 printed pages. © UCLES 2023 [Turn over
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 1 / 18 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 18 printed pages. © UCLES 2023 [Turn over
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 1 / 17 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 17 printed pages. © UCLES 2023 [Turn over
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 14 / 17 pages total, pdf
9701/42 Cambridge International AS & A Level – Mark Scheme PUBLISHED Question Answer 5(c)(ii) Marks 1 OR 4-substituted acyl / alkyl derivative ALLOW 3-substituted acyl / alkyl derivative © UCLES 2023 February/March 2023 Page 14 of 17
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 19 / 20 pages total, pdf
International AS & A Level – Mark Scheme PUBLISHED 9700/42 Question 10(a) Answer abundance / numbers / population (size) ; February/March 2023 Marks 6 Simpson’s ; genes ; alleles ; adapt / evolve ; habitats / niches ; 10(b)(i) 14 234 − 7851 ; 12 2 532 ; © UCLES 2023 Page 19 of 20
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 1 / 19 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 19 printed pages. © UCLES 2023 [Turn over
(A/s) Physics Feb/March 2023 paper 1 variant 2
Mark scheme found on page 1 / 3 pages total, pdf
February/March 2023 MARK SCHEME Maximum Mark: 40 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023
(A/s) Biology Feb/March 2023 paper 1 variant 2
Mark scheme found on page 1 / 3 pages total, pdf
February/March 2023 MARK SCHEME Maximum Mark: 40 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 13 / 17 pages total, pdf
Scheme PUBLISHED 9701/42 Question Answer February/March 2023 Marks 5(b)(ii) 3 + H+ M1 curly arrow from inside hexagon of aromatic ring to Cl + CON going to a lone pair on Cl M2 intermediate M3 curly arrow from C—H bond to inside the ring AND H+ 5(c)(i) © UCLES 2023 electrophilic substitution 1 Page 13 of 17
(A/s) Chemistry Feb/March 2023 paper 1 variant 2
Mark scheme found on page 1 / 3 pages total, pdf
February/March 2023 MARK SCHEME Maximum Mark: 40 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 12 / 20 pages total, pdf
metaphase Iattach to centromeres and arrange homologous pairs of chromosomes at the equator of the cell anaphase I(contract to) pull, centromeres / chromosomes, towards poles / to centrioles ; prophase II ;re-form spindle in daughter cells telophase II © UCLES 2023 February/March 2023 disassemble Page 12 of 20 diagram (forming) four daughter cells ; two single chromosomes inside a (re-forming) nuclear envelope ;
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 8 / 18 pages total, pdf
February/March 2023 Marks C1 1.10 105 540 10−6 1.38 10−23 300 = 1.435 1022 Ek = (3 / 2) kTN = (3 / 2) 1.38 1023 (742 – 27) 1.10 105 540 10−
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 15 / 18 pages total, pdf
and emits photon in any directionB1 hc= EC1 uses 658 nmC1 6.63 10 –34 3.00 108 = – E1 – (–3.40 × 1.60 × 10–19) –9 658 10A1 E1 = –2.42 10–19 J © UCLES 2023 February/March 2023 Page 15 of 18
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 11 / 20 pages total, pdf
February/March 2023 Marks 3 1different number of nucleotides may be deleted ; 2different genes may be deleted ; 3an individual only has one allele (of the deleted genes) ; 4different individuals may have different alleles of the same gene or in one individual remaining allele may be recessive but dominant in another individual ; 5so different proteins made ; 6ref. to individuals may have different environments ; A
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 15 / 19 pages total, pdf
February/March 2023 Guidance Alternative Method 2 for Question 6(b) F = 15cos20 − 2 gsin30 = 4.9053 *B1 Or R = 2 g cos30 − 15sin20 = 12.1902 Get = 15cos20 − 2 gsin30 = 0.3359 2 g cos30 − 15sin20 *
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 12 / 18 pages total, pdf
February/March 2023 Marks B1 (so Q = 18.2 C) C = Q/V C1 = 18.2 / 12 = 1.5 F 5(b) A1 gradient = –0.25C1 gradient = –1 / RCC1 R = 1 / (0.25 1.5 10–6)A1 = 2.7 106 or−t Q −t = e
(A/s) Mathematics Feb/March 2023 paper 1 variant 2
Mark scheme found on page 1 / 15 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 15 printed pages. © UCLES 2023 [Turn over
(A/s) Mathematics Feb/March 2023 paper 3 variant 2
Mark scheme found on page 1 / 17 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 17 printed pages. © UCLES 2023 [Turn over
(A/s) Chemistry Feb/March 2023 paper 2 variant 2
Mark scheme found on page 1 / 10 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 10 printed pages. © UCLES 2023 [Turn over
(A/s) Mathematics Feb/March 2023 paper 5 variant 2
Mark scheme found on page 1 / 15 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 15 printed pages. © UCLES 2023 [Turn over
(A/s) Mathematics Feb/March 2023 paper 2 variant 2
Mark scheme found on page 1 / 11 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 11 printed pages. © UCLES 2023 [Turn over
(A/s) Physics Feb/March 2023 paper 2 variant 2
Mark scheme found on page 1 / 12 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 12 printed pages. © UCLES 2023 [Turn over
(A/s) Physics Feb/March 2023 paper 5 variant 2
Mark scheme found on page 1 / 9 pages total, pdf
should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 9 printed pages. © UCLES 2023 [Turn over
(A/s) Biology Feb/March 2023 paper 2 variant 2
Mark scheme found on page 1 / 14 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 14 printed pages. © UCLES 2023 [Turn over
(A/s) Chemistry Feb/March 2023 paper 5 variant 2
Mark scheme found on page 1 / 8 pages total, pdf
should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 8 printed pages. © UCLES 2023 [Turn over
(A/s) Chemistry Feb/March 2023 paper 3 variant 3
Mark scheme found on page 1 / 10 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 10 printed pages. © UCLES 2023 [Turn over
(A/s) Physics Feb/March 2023 paper 3 variant 3
Mark scheme found on page 1 / 8 pages total, pdf
should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 8 printed pages. © UCLES 2023 [Turn over
(A/s) Biology Feb/March 2023 paper 3 variant 3
Mark scheme found on page 1 / 7 pages total, pdf
should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 7 printed pages. © UCLES 2023 [Turn over
(A/s) Biology Feb/March 2023 paper 5 variant 2
Mark scheme found on page 1 / 10 pages total, pdf
be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge International will not enter into discussions about these mark schemes. Cambridge International is publishing the mark schemes for the February/March 2023 series for most Cambridge IGCSE™, Cambridge International A and AS Level components and some Cambridge O Level components. This document consists of 10 printed pages. © UCLES 2023 [Turn over
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 17 / 18 pages total, pdf
February/March 2023 Marks piezo-electric crystalB1 (ultrasound) wave causes shape change / vibrations (of crystal)B1 shape change / vibrations causes e.m.f. (which is detected)B1 9(b)(i)93 VA1 9(b)(ii)2.7 107 rad s–1A1 9(c)(i)kg m–2 s–1B1 9(c)(ii) = Z / c = 1.7
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 11 / 18 pages total, pdf
February/March 2023 Marks A1 = 6.9 10–4 J 4(c)(i)towards the top of the page / towards plate PB1 4(c)(ii)F = QE and E = V / dC1 F = 1.6 10–19 250 / 0.018A1 = 2.2 10–15 N 4(c)(iii) either the force is not (
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 14 / 20 pages total, pdf
February/March 2023 1no / fewer, electrons accepted by oxygen or oxygen is the final electron acceptor ; 2no / fewer, electrons, enter / move along, electron transport chain / ETC or ETC stops ; 3no /fewer, H+ pumped into intermembrane space or no / less steep, proton gradient ; 4no / less, chemiosmosis ; 5reduced NAD / reduced FAD, not oxidised / or NAD /
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 14 / 18 pages total, pdf
February/March 2023 Marks it is zero when (plane of) probe is parallel to the (magnetic) field (lines)B1 it is maximum when (plane of) probe is perpendicular to (magnetic) field (lines)B1 6(b)(i)number density of charge carriersB1 6(b)(ii)smaller value of n so greater Hall voltage / VHB1 6(c)(36 mV corresponds to) 48 mTC1 use
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 13 / 18 pages total, pdf
February/March 2023 Marks C1 = ½ 18.2 10–6 12 A1 = 1.1 10–4 J or W = ½ CV2 (C1) = ½ 1.5 10–6 122 (A1) = 1.1 10–4 J or W = ½ Q2 / C (C1) = ½ (18.2 10
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 9 / 17 pages total, pdf
February/March 2023 Answer Marks 3(c)(ii) 1 3D structure charge 1 3(d)(i)VO2+ AND E⦵ of H2O2 is largest / most positive value OR VO2+ AND E⦵ is less positive than H2O21 3(d)(ii)+51 Question Answer Marks 4(a)(i)CH3CONH2 + 4[H] → CH3CH2NH2 + H2O1 4(a)(ii
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 9 / 19 pages total, pdf
truck: T = 0.4a For system: DF –0.2 =1.2aA1 For any two correct. For attempt to solve for TM1 From equations with correct number of relevant terms. Using their dimensionally correct DF. 1 May see a = . 3 T= A1 Allow awrt 0.133 . 2 N 15 5 © UCLES 2023 February/March 2023 Page 9 of 19
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 9 / 18 pages total, pdf
February/March 2023 Marks B2 or E = ½mv02 and v0 = x0 C1 6.4 10−3 = 1 0.130 2 0.0152 2 (2 = 438) ( = 20.9)C1 T = 2 / C1 A1 = 2 / 20.9 = 0.30 s 3(c)(i)resistive forcesB
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 11 / 17 pages total, pdf
February/March 2023 Marks 4(d)(iii)phenol1 4(d)(iv)NaOH / alkali1 4(d)(v)dyestuffs / dyes1 4(e)(i)species that uses one lone pair of electrons1 that forms a single dative covalent bond to a central metal atom / ion1 correct 3D cis isomer1 correct 3D trans isomer1 4(e)(iii)61 4(f)(i)units = mol–4 dm12
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 18 / 18 pages total, pdf
February/March 2023 Marks brighter star could be closer (to Earth)B1 brighter star could have a greater luminosity (in the visible wavelengths)B1 10(b)object with known luminosityB1 10(c)(i)660.9 − 656.3 v leading to 2.1 106 m s–1 8 656.3 3.0 10B1 10(c)(ii)v = HodC1 d
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 20 / 20 pages total, pdf
in the sea / oil spills / eutrophication 6there are more species of fish than there are species of mammals ; increased ocean temperatures / predatory species moving into new areas now water is warmer mammals: © UCLES 2023 February/March 2023 7more conservation projects for mammals / AW ; ora for fish 8laws in place, banning hunting / protecting mammals ; 9AVP ; Page 20 of 20
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 16 / 20 pages total, pdf
photolysis / location of oxygen-evolving complex ; 7thylakoids stacked to form grana ; 8gives large surface area ; 9thylakoid space or lumen to, form proton gradient / have high concentration of protons ; 10 thylakoid membrane is (relatively) impermeable, to maintain the proton gradient ; 11 ATP synthase to make ATP; 12 chemiosmosis ; © UCLES 2023 February/March 2023 Page 16 of 20
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 5 / 19 pages total, pdf
February/March 2023 Abbreviations AEF/OEAny Equivalent Form (of answer is equally acceptable) / Or Equivalent AGAnswer Given on the question paper (so extra checking is needed to ensure that the detailed working leading to the result is valid) CAOCorrect Answer Only (emphasising that no ‘follow through’ from a previous error is allowed) CWOCorrect Working Only ISWIgnore Subsequent Working SOISeen Or Implied SCSpecial Case (detailing the mark to be
(A/s) Physics Feb/March 2023 paper 1 variant 2
Mark scheme found on page 3 / 3 pages total, pdf
Cambridge International AS & A Level – Mark Scheme February/March 2023 PUBLISHED 9702/12 Question Answer Marks 29A1 30D1 31A1 32B1 33B1 34A1 35B1 36A1 37C1 38C1 39A1 40A1 © UCLES 2023 Page 3 of 3
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 17 / 17 pages total, pdf
10–3] ÷ [2.0 10–3] [H+] = 2.65 10–6 ecf1 M4 pH = –log(2.65 10–6) = 5.58 / 5.6 ecf on a calculated and identified [H+]1 ALLOW alternative approach using Henderson-Hasselbalch equation for M3 and M4 © UCLES 2023 February/March 2023 Page 17 of 17
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 16 / 18 pages total, pdf
February/March 2023 Marks 234, 92 for the uranium nucleusB1 4, 2 for the alpha particleB1 N0 = 0.874 / (238 1.66 10–27)A1 = 2.21 1024 8(b)(ii) A = N = C1 A1 ln2 2.21 1024 87.7 365 24 3
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 8 / 20 pages total, pdf
February/March 2023 Marks 3 max two from: 1(phenotype has) range of values / intermediates ; 2(phenotypes) not, in groups / in classes / categoric / discrete / qualitative or (phenotypes are) quantitative ; 3normal distribution ; max two from: 3(b)(i) 4polygenic / controlled by many genes ; 5different genes / alleles, have additive effect ; 6(named) environmental factors (contribute to
(A/s) Biology Feb/March 2023 paper 1 variant 2
Mark scheme found on page 3 / 3 pages total, pdf
Cambridge International AS & A Level – Mark Scheme February/March 2023 PUBLISHED 9700/12 Question Answer Marks 29C1 30A1 31A1 32B1 33C1 34C1 35B1 36C1 37B1 38A1 39D1 40C1 © UCLES 2023 Page 3 of 3
(A/s) Mathematics Feb/March 2023 paper 5 variant 2
Mark scheme found on page 6 / 15 pages total, pdf
February/March 2023 Guidance B1 All cumulative frequencies stated. May be under data table, condone omission of 4. May be read accurately from graph, must include 4. 60 M1 At least 5 points plotted at class upper end points, daylight rule tolerance. Linear cf scale 0 ⩽ cf ⩽ 60, linear time scale 30 ⩽ time ⩽ 240 with at least 3 values identified on each
(A/s) Chemistry Feb/March 2023 paper 1 variant 2
Mark scheme found on page 3 / 3 pages total, pdf
Cambridge International AS & A Level – Mark Scheme February/March 2023 PUBLISHED 9701/12 Question Answer Marks 29D1 30A1 31D1 32B1 33A1 34D1 35C1 36A1 37B1 38C1 39B1 40B1 © UCLES 2023 Page 3 of 3
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 5 / 20 pages total, pdf
February/March 2023 any three from: 3 1(aquaporins are) water channel (proteins) ; 2(more) aquaporins increase (cell surface) membrane permeability (to water) ; ora 3of collecting duct (cells) ; I distal convoluted tubule cells 4allow water to, be reabsorbed / move into tissue fluid or blood ; any three from: 3 1detected by osmoreceptors ; 2in hypothalamus ; 3(osmoreceptors send) fewer impulses
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 10 / 17 pages total, pdf
February/March 2023 Marks (least) phenylamine < ammonia < ethylamine (most)1 explanation • (order of basicity) ability of base AND to accept a proton OR donate its lone pair (to a proton) phenylamine • lone pair / p-orbital from N delocalised / overlaps with (-)ring / benzene ethylamine • alkyl / ethyl group is electron donating group / +I group3 • increases electron density on
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 12 / 17 pages total, pdf
February/March 2023 Marks 4(f)(iv)CH3NH2 (is basic so) reacts with water to produce OH– that reacts with Cd2+ OR CH3NH2 acts as a base and accepts a proton from Cd[H2O)6]2+ / water OR [Cd(H2O)6]2+ + 4CH3NH2 → [Cd(OH)4(H2O)2]2– + 4CH3NH3+ OWTTE1 4(f)
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 7 / 18 pages total, pdf
February/March 2023 Answer Marks gas for which pV TM1 where T is thermodynamic temperatureA1 evidence of two temperature conversions between C and KB1 two calculations shown, one for each state e.g.A1 1.10 105 540 10−6 6.70 106 30 10−6 = 0.198 and = 0.198 ( 273
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 10 / 20 pages total, pdf
February/March 2023 Marks 3 1ref. to isolate / extract, DNA, from, cells / tissue / named ; 2ref. to cut DNA, into small fragments / using restriction enzymes ; 3ref. to denature / AW, into single-stranded DNA ; 4add fluorescent, tag / marker / dye ; 4(b)(i)2 400 000 or 2 500 000 ;1 4(b)(ii
(A/s) Chemistry Feb/March 2023 paper 3 variant 3
Mark scheme found on page 10 / 10 pages total, pdf
Cambridge International AS & A Level – Mark Scheme PUBLISHED 9701/33 Question Answer 3(e) cation © UCLES 2023 Marks anion FA 5Cu2+ / copper(II)CO32– / carbonate FA 6H+ / hydrogenCl – / chloride Any 2 correct identities = 1 mark Page 10 of 10 February/March 2023 2
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 17 / 20 pages total, pdf
February/March 2023 Marks 4 describe 1 A activity increases and B activity remains, low / constant ; 2 comparative data quote ; e.g. 3.0–3.2 at 0.5 mins and 11.4–11.6 at 6 mins for A 0.4 throughout for B max three: explanation: 3RA / rubisco activase, activates rubisco ; 4by changing the active site of rubisco ; 5by enabling rubisco
(A/s) Chemistry Feb/March 2023 paper 2 variant 2
Mark scheme found on page 10 / 10 pages total, pdf
Cambridge International AS & A Level – Mark Scheme PUBLISHED 9701/22 Question 4(d)(i) 4(d)(ii) © UCLES 2023 Answer February/March 2023 Marks G1 (absorption at) 2200–2250 (cm–1) AND C≡N1 3.4 AND relative abundance of 79Br:81Br ≅ 50:50 OR 1:11 Page 10 of 10
(A/s) Biology Feb/March 2023 paper 1 variant 2
Mark scheme found on page 2 / 3 pages total, pdf
February/March 2023 PUBLISHED 9700/12 Question Answer Marks 1A1 2C1 3C1 4B1 5D1 6C1 7A1 8B1 9A1 10D1 11C1 12D1 13B1 14A1 15B1 16B1 17D1 18B1 19A1 20C1 21C1 22B1 23D1 24C1 25A1 26D1 27D1
(A/s) Physics Feb/March 2023 paper 1 variant 2
Mark scheme found on page 2 / 3 pages total, pdf
February/March 2023 PUBLISHED 9702/12 Question Answer Marks 1C1 2B1 3A1 4B1 5B1 6D1 7D1 8C1 9D1 10C1 11C1 12B1 13D1 14D1 15B1 16C1 17B1 18C1 19B1 20D1 21A1 22A1 23D1 24B1 25C1 26D1 27B1
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 13 / 20 pages total, pdf
February/March 2023 Answer Marks 6(a)(i)D;1 6(a)(ii)D and C ;1 6(b)any three from:3 © UCLES 2023 1site of, link reaction / Krebs cycle ; 2DNA / ribosomes, for production of proteins (used in respiration) ; 3named example ; e.g. enzymes / coenzymes / electron carriers ; 4production of, reduced FAD / reduced NAD, for
(A/s) Chemistry Feb/March 2023 paper 1 variant 2
Mark scheme found on page 2 / 3 pages total, pdf
February/March 2023 PUBLISHED 9701/12 Question Answer Marks 1D1 2D1 3B1 4A1 5D1 6A1 7B1 8C1 9B1 10D1 11C1 12C1 13C1 14D1 15C1 16A1 17A1 18B1 19A1 20B1 21B1 22C1 23D1 24D1 25D1 26B1 27A1
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 16 / 19 pages total, pdf
February/March 2023 Guidance Attempt to use conservation of energy 1 1 2 2 2 0.5v = 0.5 g 1.8 or 2 mv = mg 1.8 M1 2 terms, dimensionally correct. Do not allow from use of constant acceleration. v=6A1 Do not allow from use of constant acceleration. Attempt at conservation
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 6 / 18 pages total, pdf
February/March 2023 Marks work done per unit massB1 work (done on mass) moving mass from infinity (to the point)B1 1(b)(i)–3.55 107 J kg–1B1 1(b)(ii) =−GM rB1 1(a) M =– −3.55 107 4 800 000 6.67 10−11 = 2.55 10
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 16 / 17 pages total, pdf
February/March 2023 Marks 5(f)(i)ten / 101 5(f)(ii)( = 0.9–1.7) • 9H • singlet • –CH3 / alkane ( = 3.2–4.0) / ( = 2.3–3.0) • 1H • triplet • –CHO / alkyl next to electronegative atom OR Ar-CH / alkyl next to aromatic ring ( = 6.0–9
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 9 / 20 pages total, pdf
February/March 2023 Marks 3 any two from: 3(b)(iii) © UCLES 2023 3overlap in, data range / error bars ; 4ref. to correlation does not prove causation ; 5only a single investigation / needs repeating / small sample size ; 6ref. to this is only at 5% probability so may not actually be different / AW ; 7t-test may not be valid due
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 18 / 20 pages total, pdf
February/March 2023 Marks 4 1competes with, acetylcholine / neurotransmitter or acetylcholine cannot bind to receptors or blocks receptors ; 2Na+ channels do not open or no / fewer, sodium ions enter (muscle fibre) ; 3so, no / less, depolarisation of sarcolemma ; 4no / fewer, action potentials / impulses (spread across muscle fibre) ; 5Ca2+ (voltage-gated) channels do not open in sarcoplasmic
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 15 / 20 pages total, pdf
from: 3 sensory © UCLES 2023 February/March 2023 motor 1cell body, between dendron and axon / in ganglionandcell body, at end / in CNS ; 2has dendron and axonandhas (long) axon ; 3no dendrites from cell bodyanddendrites extend from cell body ; 4carries impulses from receptor to, CNS / intermediate neuroneandcarries impulses from, CNS / intermediate neurone, to effector ; Page 15 of 20
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 19 / 19 pages total, pdf
+ 0.4 + 0.4 = 4 b = 6 3 c 7−c 1 c = OR + 0.7 + 0.4 + 0.4 = 2 4 3 Distance from B = 6 A1 2 m 3 5 © UCLES 2023 February/March 2023 Page 19 of 19
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 7 / 20 pages total, pdf
February/March 2023 Answer Marks 2(a)(iv)IFN- is, unstable / breaks down ;1 2(b)(only E. coli that have taken up the plasmid) will, grow / survive, in the presence of, ampicillin / antibiotic ;1 2(c)any five from:5 © UCLES 2023 1(random) mutation ; 2natural selection / directional selection ; 3antibiotic acts as selection pressure / AW ;
(A/s) Physics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 10 / 18 pages total, pdf
February/March 2023 Marks (electric) force is (directly) proportional to product of chargesB1 force (between point charges) is inversely proportional to the square of their separationB1 arrows showing tension upwards in direction of string, electric force horizontally to the right and weight vertically downwards and all three labelledB1 FE = 96 10−9 64 10−9 4 8.85
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 5 / 17 pages total, pdf
February/March 2023 Marks 1 ↿⇂ 1(a)(ii) 3 one ● for each of the eight species (including state symbol) on the correct line AND one ● e– any three [1] any six [2] all nine [3] 1(a)(iii) •EA becomes less negative/ less exothermic (down group / S to Te) •atomic radii increases OR outer shell gets farther from nucleus OR
(A/s) Chemistry Feb/March 2023 paper 5 variant 2
Mark scheme found on page 8 / 8 pages total, pdf
– 1.00) / 1.00] 100 Marks 1 (assuming 2(d)(iv) is 1.10) = [(1.10 – 1.00) / 1.00] 100 = 10% (10% > maximum percentage error / 5.25% ) AND other factors (beyond measurement caused the error) © UCLES 2023 February/March 2023 Page 8 of 8
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 8 / 19 pages total, pdf
February/March 2023 Guidance Attempt at integration of their v 5 8 ( s = ) = 3 t 2 = 16 t 2 ( +c ') 2.5 15 *M1 Increasing power by 1 and a change in coefficient in at least one term; may be unsimplified. s = vt M0 Their v , which has come from integration in part
(A/s) Physics Feb/March 2023 paper 4 variant 2
Question paper found on page 1 / 32 pages total, pdf
February/March 2023 2 hours You must answer on the question paper. No additional materials are needed. INSTRUCTIONS ● Answer all questions. ● Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs. ● Write your name, centre number and candidate number in the boxes at the top of the page. ● Write your answer to each question in the space provided.
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 6 / 19 pages total, pdf
February/March 2023 Guidance M1 Use of power = ∆W / ∆t to get an equation in t . May see 600v = 4500 v = 7.5 followed by 7.5t = 15 . t =2s A1 2 1(b) 600 = 200a a = 3 0= *M1 Use of Newton’s second law; 2 terms only
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 12 / 19 pages total, pdf
February/March 2023 Guidance Attempt to resolve vertically and horizontallyM1 3 terms vertically and 2 terms horizontally; allow sign errors; allow g missing. Must have TA = 0 . TB cos 45 + 500 − 100 g = 0 and F − TB sin 45 = 0A1 Allow −TB cos 45 + 500 − 100 g = 0 and F + TB sin 45
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 18 / 19 pages total, pdf
February/March 2023 FT their 2 from (b), t = 2 0.8 . their 2 u+v For use of s = t to get a time up the slope. 2 Allow for total time on slope from 1 0 = ( their 2 ) t − ( their a ) t 2 t = 0.8 . 2 Distance between P moved is (
(A/s) Biology Feb/March 2023 paper 4 variant 2
Question paper found on page 1 / 28 pages total, pdf
February/March 2023 2 hours You must answer on the question paper. No additional materials are needed. INSTRUCTIONS ● Answer all questions. ● Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs. ● Write your name, centre number and candidate number in the boxes at the top of the page. ● Write your answer to each question in the space provided.
(A/s) Physics Feb/March 2023 paper 2 variant 2
Mark scheme found on page 9 / 12 pages total, pdf
February/March 2023 Marks E = ½mv2C1 p = mvC1 m = 0.372 / (2 0.30) or 0.37 / 1.6 or (0.30 2) / 1.62A1 = 0.23 kg 4(b) 0.37 – 0.65 = –0.13 – p A1 p = 0.15 kg m s–1 4(c) 7
(A/s) Biology Feb/March 2023 paper 4 variant 2
Mark scheme found on page 6 / 20 pages total, pdf
February/March 2023 Marks 2 3 concentration of IFN- produced 2(a)(iii) 1increases steeply (after addition of IPTG) ; 2peak is, at 8 hours / 4 hours (after addition of IPTG) ; 3decrease is less steep or final concentration greater than starting concentration / AW ; 4data quote ; any one from: 1 IPTG is higher / lactose is lower, because © UCLES 2023
(A/s) Mathematics Feb/March 2023 paper 1 variant 2
Mark scheme found on page 11 / 15 pages total, pdf
February/March 2023 Marks 4 4 3 or sin BDC = or cos BDC = used to find ADC 3 5 5 Guidance M1 May use cosine rule or CAD = tan −1 4 . 8 BDC = 0.927 3 → ADC = π − 0.927 3 [= 2.214 to 2.215 ]A1 Allow degrees, 126.87, and 0.7
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 13 / 19 pages total, pdf
February/March 2023 Marks Guidance Attempt at LamiM1 Allow sign errors. TB 100 g − 500 F = = sin135 sin135 sin 90 A1 F = 500A1 awrt 500 to 3sf. 500 − 100 g F 100 g − 500 F or or = = sin135 sin135 sin 45 sin
(IGCSE) Mathematics Oct/Nov 2010 paper 3 variant 1
Question paper found on page 5 / 16 pages total, pdf
February. January February March (i) Complete the key for the pictogram. [1] (ii) Complete the pictogram for March. [1] (e) Priya draws a scatter diagram to find the correlation between rainfall and sunshine for January to June. (i) Complete the scatter diagram below. January and February are plotted for you. 90 80 70 60 50 40 0123 Average daily sunshine (hours)
(A/s) Physics Feb/March 2023 paper 2 variant 2
Mark scheme found on page 6 / 12 pages total, pdf
February/March 2023 Marks 1(a)only ampere and kelvin underlinedB1 1(b)initial speed / velocity is zeroB1 (non-zero magnitude of) acceleration is constant / uniform (and in a straight line)B1 a = 2.752 / (2 3.89)A1 1(c)(i) = 0.97 m s–2 1(c)(ii) percentage uncertainty = (2 0.8) + 0
(A/s) Physics Feb/March 2023 paper 2 variant 2
Mark scheme found on page 8 / 12 pages total, pdf
February/March 2023 Marks resultant force (in any direction) is zeroB1 resultant moment/torque (about any point) is zeroB1 3(b)(component =) 17sin50 = 13 (N) or 17cos40 = 13 (N)A1 3(c)(W 0.25) or (12 0.35) or (13 0.50)C1 (W 0.25) +
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 3 / 19 pages total, pdf
February/March 2023 Mathematics Specific Marking Principles 1Unless a particular method has been specified in the question, full marks may be awarded for any correct method. However, if a calculation is required then no marks will be awarded for a scale drawing. 2Unless specified in the question, answers may be given as fractions, decimals or in standard form. Ignore superfluous zeros, provided that the degree of accuracy is not
(A/s) Mathematics Feb/March 2023 paper 1 variant 2
Mark scheme found on page 14 / 15 pages total, pdf
February/March 2023 Guidance B1 d2 y 1 − 32 =− x dx 2 2 < 0 (or −4 ) hence Maximum DB1 WWW Ignore extra solutions from x = − 2 Question Answer 11(a) Gradient of AB = Marks 2 − ( −1) Guidance M1 Expect 1, must be from y / x . 5−2 Equation of AB is y − 2 =
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 10 / 19 pages total, pdf
February/March 2023 Marks Guidance Attempt to resolve verticallyM1 4 terms; allow with TA and TB ; allow sign errors; allow g missing. 500 + T cos 45 + T cos 45 − 100 g = 0A1 Must have TA = TB = T . Allow if 500 − 2T cos 45 − 100 g = 0 . Allow 500 − TA cos 4
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 8 / 17 pages total, pdf
February/March 2023 Marks 2(c)(iii)mol–2 dm6 s–11 2(c)(iv)t½ = 0.693 / 8.25 10–5 = 8400 (s) OR t½ = In2 / 8.25 10–5 = 8401.8 (s)1 2(c)(v)(k1) increases (with temperature)1 2(d)• • •2 reactants adsorb (to
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Question paper found on page 1 / 28 pages total, pdf
February/March 2023 2 hours You must answer on the question paper. No additional materials are needed. INSTRUCTIONS ● Answer all questions. ● Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs. ● Write your name, centre number and candidate number in the boxes at the top of the page. ● Write your answer to each question in the space provided.
(A/s) Mathematics Feb/March 2023 paper 4 variant 2
Mark scheme found on page 7 / 19 pages total, pdf
February/March 2023 Guidance 1 Use of s = ut + at 2 for either. 2 Allow if a not substituted, need both expressions with opposite sign of t 2 term and the same a . DM1 Allow sP + sQ = 18 . Must have s P and sQ of the correct form. So height = 10.8 m A1 Alternative method for Question 2(b): Using relative
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 6 / 17 pages total, pdf
February/March 2023 Marks 1(b)(i)S negative AND more moles / molecules of gaseous reactants ORA OR S negative AND moles / molecules of gas are reduced (in the reaction)1 1(b)(ii)S = 50.8 + 197.7 – 43.7 – 5.71 1(b)(iii)G = H – TS = (+)199.1 (J K–1
(A/s) Chemistry Feb/March 2023 paper 4 variant 2
Mark scheme found on page 7 / 17 pages total, pdf
February/March 2023 Answer Marks 2(b)(iii) 3 • • • • • • • • • Pt(s) / C / graphite Cr(s) H+(aq) / any strong acid Cr3+(aq) H2(g) voltmeter / V salt bridge labelled conditions of 1 atm AND 1 mol dm–3 / 1 M / 1 mol / dm3 other liquid level (salt bridge) and wire to
(IGCSE) Physics Feb/March 2022 paper 4 variant 2
Mark scheme found on page 1 / 17 pages total, pdf
IGCSE™ PHYSICS 0625/42 Paper 4 Extended Theory February/March 2022 MARK SCHEME Maximum Mark: 80 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began, which
(IGCSE) Biology Feb/March 2022 paper 4 variant 2
Mark scheme found on page 1 / 12 pages total, pdf
IGCSE™ BIOLOGY 0610/42 Paper 4 Theory (Extended) February/March 2022 MARK SCHEME Maximum Mark: 80 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
(IGCSE) Geography Feb/March 2022 paper 4 variant 2
Mark scheme found on page 1 / 9 pages total, pdf
IGCSE™ GEOGRAPHY 0460/42 Paper 4 Alternative to Coursework February/March 2022 MARK SCHEME Maximum Mark: 60 Published This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began,
(A/s) Chemistry Feb/March 2023 paper 2 variant 2
Mark scheme found on page 8 / 10 pages total, pdf
February/March 2023 Marks 1 curly arrow from lone pair on C of CN– to C(δ+) 3(b)(ii) 3(b)(iii) correct dipole on C=O AND curly arrow from C=O bond to Oδ–1 correct organic intermediate1 curly arrow from lone pair on alkoxide O(–) to H+ / H of HCN / H of H2O (to reform the alcohol)1 acidified K