(A/s) Biology May/June 2023 paper 2 variant 3
Mark scheme found on page 19 / 20 pages total, pdf
protein synthesis polypeptide folding (in lumen) ; A protein folding packaged in / formation of, transport vesicles / vesicles for transport, to Golgi body ; Golgi body packaging into, Golgi / secretory, vesicles ; A formation of, Golgi / secretory vesicle, containing glycoprotein A packaging into vesicles for transport to cell surface membrane rough endoplasmic reticulum or Golgi body (modification by) glycosylation (of protein) / described ; e.g
(A/s) Biology Oct/Nov 2018 paper 2 variant 3
Mark scheme found on page 5 / 16 pages total, pdf
folding of polypeptides / protein folding assembly of polypeptides to form quaternary structure addition of (named) prosthetic group addition of sugars / addition of carbohydrate / glycosylation cutting of polypeptides removal of, methionine / first amino acid making proteins functional 3 packaging into vesicles / formation of Golgi vesicles / formation of secretory vesicles ; A ‘budding off’ / ‘breaking off’ / transport proteins in Golgi vesicles 4 formation of (primary)
(A/s) Biology Oct/Nov 2012 paper 2 variant 1
Mark scheme found on page 3 / 7 pages total, pdf
protein / polypeptide, synthesis translation modification of protein / described (e.g. folding, glycosylation) protein transport (to Golgi) ecf if RER F Golgi (body / complex /apparatus) one from ; modification of protein glycosylation / described modification of lipid pack(ag)ing (of), protein / lipids production of, (Golgi / secretory) vesicles / lysosomes ignore synthesis of protein allow ecf if smooth endoplasmic reticulum G lysosome or
(A/s) Biology Oct/Nov 2012 paper 2 variant 3
Mark scheme found on page 3 / 8 pages total, pdf
protein / glycosylation / described modification of lipid pack(ag)ing (of), protein / lipids production of (Golgi / secretory) vesicles / lysosomes ignore synthesis of protein (incorrect name) lysosome function = contains / storage of hydrolytic / digestive, enzymes Golgi / secretory, vesicles = transport, protein / lipids C name chloroplast(s) ; function (site of) ; photosynthesis light-dependent, reactions / stage (of photosynthesis) light,
(A/s) Biology May/June 2004 paper 6
Mark scheme found on page 21 / 42 pages total, pdf
folding / shape of protein ; detail of affect of protein changes ; 2 named example e.g. PKU ; R sickle cell anaemia lack of enzyme / non functioning enzyme ; 2 x phenotype changes / symptoms ;; 3 chromosome mutation ; detail of mutation ; named example e.g. Down’s syndrome ; 2 x symptoms ;; 4 max (b) homozygotes for sickle cell allele die from sickle cell anaemia
(A/s) Biology May/June 2004 paper 3
Mark scheme found on page 21 / 42 pages total, pdf
folding / shape of protein ; detail of affect of protein changes ; 2 named example e.g. PKU ; R sickle cell anaemia lack of enzyme / non functioning enzyme ; 2 x phenotype changes / symptoms ;; 3 chromosome mutation ; detail of mutation ; named example e.g. Down’s syndrome ; 2 x symptoms ;; 4 max (b) homozygotes for sickle cell allele die from sickle cell anaemia
(A/s) Biology May/June 2004 paper 2
Mark scheme found on page 21 / 42 pages total, pdf
folding / shape of protein ; detail of affect of protein changes ; 2 named example e.g. PKU ; R sickle cell anaemia lack of enzyme / non functioning enzyme ; 2 x phenotype changes / symptoms ;; 3 chromosome mutation ; detail of mutation ; named example e.g. Down’s syndrome ; 2 x symptoms ;; 4 max (b) homozygotes for sickle cell allele die from sickle cell anaemia
(A/s) Biology May/June 2004 paper 5
Mark scheme found on page 21 / 42 pages total, pdf
folding / shape of protein ; detail of affect of protein changes ; 2 named example e.g. PKU ; R sickle cell anaemia lack of enzyme / non functioning enzyme ; 2 x phenotype changes / symptoms ;; 3 chromosome mutation ; detail of mutation ; named example e.g. Down’s syndrome ; 2 x symptoms ;; 4 max (b) homozygotes for sickle cell allele die from sickle cell anaemia
(A/s) Biology May/June 2004 paper 1
Mark scheme found on page 21 / 42 pages total, pdf
folding / shape of protein ; detail of affect of protein changes ; 2 named example e.g. PKU ; R sickle cell anaemia lack of enzyme / non functioning enzyme ; 2 x phenotype changes / symptoms ;; 3 chromosome mutation ; detail of mutation ; named example e.g. Down’s syndrome ; 2 x symptoms ;; 4 max (b) homozygotes for sickle cell allele die from sickle cell anaemia
(A/s) Biology May/June 2004 paper 4
Mark scheme found on page 21 / 42 pages total, pdf
folding / shape of protein ; detail of affect of protein changes ; 2 named example e.g. PKU ; R sickle cell anaemia lack of enzyme / non functioning enzyme ; 2 x phenotype changes / symptoms ;; 3 chromosome mutation ; detail of mutation ; named example e.g. Down’s syndrome ; 2 x symptoms ;; 4 max (b) homozygotes for sickle cell allele die from sickle cell anaemia
(A/s) Biology Oct/Nov 2020 paper 1 variant 2
Question paper found on page 6 / 16 pages total, pdf
protein Bis the order of amino acids present in a protein encoded by DNAis the shape formed by folding of a polypeptide and held together by hydrogen bondscontains two types of polypeptide that interact forming the shape of a protein Cis the result of translation of an mRNA molecule by a ribosome into a chain of amino acidsis the result of ionic and hydrogen bonds, disulfide bridges and hydrophobic interactions between amino acidsis formed by
(A/s) Biology Oct/Nov 2010 paper 2 variant 2
Mark scheme found on page 3 / 9 pages total, pdf
folding / complex 3D shape ; 3 formation of named bond(s) ; R if peptide bond in list 4 quaternary structure / description (e.g. assembly of polypeptides) ; 5 glycosylation / formation of glycoproteins / addition of carbohydrate(s) or sugar(s) ; R hydrocarbon chain 6 addition of, non-protein portion(s) / prosthetic group(s) / named example ; A haem / iron / Fe /
(A/s) Biology Oct/Nov 2021 paper 4 variant 1
Mark scheme found on page 15 / 21 pages total, pdf
any four from: Marks 4 1base / nucleotide, insertion / deletion / substitution ; 2frameshift / changed reading frame ; 3ref. to stop codon ; 4changes / different, primary structure / amino acid sequence ; 5changes / different, folding / 3D shape / 3o structure, of enzyme / protein ; 6active site does not, bind / fit, substrate / complex molecules ; Page 15 of 21
(A/s) Biology Oct/Nov 2021 paper 4 variant 3
Mark scheme found on page 15 / 21 pages total, pdf
any four from: Marks 4 1base / nucleotide, insertion / deletion / substitution ; 2frameshift / changed reading frame ; 3ref. to stop codon ; 4changes / different, primary structure / amino acid sequence ; 5changes / different, folding / 3D shape / 3o structure, of enzyme / protein ; 6active site does not, bind / fit, substrate / complex molecules ; Page 15 of 21
(A/s) Chemistry May/June 2015 paper 4 variant 2
Mark scheme found on page 8 / 10 pages total, pdf
[3] M1 the pH of that area of the protein would change M2 protein becomes less hydrophilic / soluble or more hydrophobic M3 fewer hydrogen bonds or more van der Waals’ (id–id) forces M4 fewer ionic bonds form M5 the tertiary structure / folding / (3D) shape (of the protein) would change M6 the active site would be different / less efficient [Total: 8]
(A/s) Biology May/June 2021 paper 2 variant 1
Mark scheme found on page 9 / 16 pages total, pdf
folding of, amylase / polypeptide / protein ; 2 between, R groups with amine and carboxyl groups ; A between R groups with -NH and, -CO / -OH 3 idea that may be between amino acids far apart in primary structure ; 4 either helps to maintain / form / AW, globular shape / 3D shape / structure (of amylase / polypeptide / protein) or maintains / forms / AW,
(A/s) Biology May/June 2021 paper 1 variant 3
Question paper found on page 7 / 20 pages total, pdf
protein Bis the order of amino acids present in a protein encoded by DNAis the coiling of a chain of amino acids to form a -pleated sheet or an -helixis the shape formed by the folding of a polypeptide and is held together by hydrogen bondscontains two types of polypeptide that interact forming the shape of a protein Cis the result of translation of an mRNA molecule by a ribosome into a chain
(A/s) Biology Oct/Nov 2021 paper 1 variant 3
Question paper found on page 5 / 20 pages total, pdf
protein encoded by DNAthe coiling of a chain of amino acids to form a -pleated sheetthe shape formed by folding of a polypeptide and held together by hydrogen bonds Cthe result of translation of an mRNA molecule by a ribosome into a chain of amino acidsoccurs because of attraction between hydrogen and oxygen atoms in the side chainsthe result of ionic and hydrogen bonds, disulfide bridges and hydrophobic interactions between amino acids Dthe sequence
(A/s) Biology May/June 2021 paper 4 variant 2
Mark scheme found on page 21 / 22 pages total, pdf
folding ; 7loss of function in protein or enzyme / example described ; 8(premature) stop codon ; Huntinton’s disease 9 (mutant allele) is dominant ; 10 HD / dominant, allele has more repeats of base triplet CAG (than normal) ; 11 heterozygote will have disease ; 12 brain cells die more rapidly (than normal) / brain degeneration ; 13 involuntary movements / mental deterioration or described /
(A/s) Biology Oct/Nov 2007 paper 2
Mark scheme found on page 2 / 5 pages total, pdf
/ stores (oxygen binds to) iron ion / Fe 2+ / Fe II (in haem) ; A atom, of iron / ferum [3] (ii) tertiary (each) polypeptide / protein, with complex 3D shape ; folding of secondary structure / folded alpha helices ; polypeptide / protein, coiled / folded / curled up / compact ; 1 max quaternary more than one polypeptide / AW ; [2]
(A/s) Chemistry May/June 2010 paper 4 variant 3
Mark scheme found on page 7 / 9 pages total, pdf
folding of the protein / polypeptide chain due to interactions between side-chains on the amino acids or the structure which gives the protein its 3-D / globular shape (1) [2] (b) (i) Diagram: Minimum is CH 2 S-SCH 2 (1) (ii) Oxidation / dehydrogenation / redox (1) (iii) Hydrogen / H bonds; ionic interactions / bonds or ion-dipole or salt bridges; van
(A/s) Chemistry May/June 2010 paper 4 variant 2
Mark scheme found on page 7 / 9 pages total, pdf
folding of the protein / polypeptide chain due to interactions between side-chains on the amino acids or the structure which gives the protein its 3-D / globular shape (1) [2] (b) (i) Diagram: Minimum is CH 2 S-SCH 2 (1) (ii) Oxidation / dehydrogenation / redox (1) (iii) Hydrogen / H bonds; ionic interactions / bonds or ion-dipole or salt bridges; van
(A/s) Biology May/June 2019 paper 2 variant 1
Mark scheme found on page 5 / 13 pages total, pdf
folding / coiling, of, (each) polypeptide chain(s) / secondary structure ; R idea of polypeptide chains interacting (quaternary structure) 4 ref. to globular A description, e.g. spherical I circular / round or ref. to 3D, shape / structure ; A 3D arrangement 1(b)(i) X – site of synthesis of, (light and heavy) polypeptides ; A protein(s) A transport / modification,
(A/s) Biology May/June 2006 paper 2
Mark scheme found on page 4 / 6 pages total, pdf
protein); different, sequences of amino acids / primary structures; ref to, folding of the molecule / secondary structure / tertiary structure; [max 3] (e) poor sanitation / no treatment of faecal waste; contamination of (drinking) water supply; poverty / poor living conditions / poor hygiene / poor (health) education; ref to natural disasters; e.g. assistance / aid / medical help / AW, cannot arrive
(A/s) Biology May/June 2017 paper 4 variant 2
Mark scheme found on page 6 / 19 pages total, pdf
bp ; 4(b)(ii) 1. after folding substituted amino acids are close together ; 2. ref. to different bonding ; 3. (substituted amino acids) causes change to protein, 3D / tertiary / quaternary / globular, structure ; 4. herbicide / inhibitor, unable to bind to, active / allosteric, site ; © UCLES 2017 May/June 2017 1 Page 6 of 19 max 2
(A/s) Biology May/June 2021 paper 2 variant 2
Mark scheme found on page 13 / 23 pages total, pdf
folding / coiling, to form tertiary / 3° / third level, structure ; A ref. to 3D structure as alternative to, folding / coiling A secondary structure, folds / coils, to form tertiary structure R alpha helix / beta-pleated sheet, coils / folds 3two of hydrogen bonds / ionic or electrostatic bonds / disulfide bonds or bridges / hydrophobic interactions ; I peptide bonds as part of a list
(A/s) Thinking Skills Oct/Nov 2009 paper 1 variant 2
Question paper found on page 14 / 20 pages total, pdf
folding a sheet of A4 size paper as shown below. The paper is printed on both sides before folding. BACK FRONT Which of the layouts below shows the correct positions of the front and back page? A B C BACK BACK top top top top top top FRONT FRONT FRONT BACK D E BACK top © UCLES 2009 top top top BACK FRONT FRONT 9694/12/O/N/09
(A/s) Thinking Skills Oct/Nov 2009 paper 1 variant 1
Question paper found on page 3 / 20 pages total, pdf
folding a sheet of A4 size paper as shown below. The paper is printed on both sides before folding. BACK FRONT Which one of the layouts below shows the correct positions of the front and back page? A B C BACK BACK top top top top top top FRONT FRONT FRONT BACK D E BACK top © UCLES 2009 top top top BACK FRONT FRONT 9694/11/O/N/0
(IGCSE) Design and Technology May/June 2014 paper 3 variant 1
Question paper found on page 5 / 16 pages total, pdf
.......................................................[2] 8 Fig. 6 shows folding bars. Fig. 6 Add to Fig. 6 to show a piece of sheet metal being bent to shape in the folding bars. © UCLES 2014 0445/31/M/J/14 [3] [Turn over
(A/s) Biology Oct/Nov 2013 paper 2 variant 1
Mark scheme found on page 8 / 10 pages total, pdf
protein / biological molecules / polymers / AW intracellular movement of vesicles exocytosis / endocytosis / bulk transport active transport [3] (b) (i) lipoproteins are soluble ; cholesterol is not water-soluble ; cholesterol surrounded by / lipoproteins have, phospholipid heads / proteins, that are hydrophilic ; AW allows transport in blood ; [max 1] (ii) cholesterol needed for making / components of, membranes ; membrane stability ; regulating
(A/s) Thinking Skills May/June 2005 paper 1
Question paper found on page 9 / 32 pages total, pdf
folding a sheet of A4 paper as shown below. The paper is printed on both sides before folding. BACK FRONT Which of the layouts below shows the correct positions of the front and back page? A B C BACK BACK top top top top top top FRONT FRONT FRONT BACK D E BACK top © UCLES 2005 top top top BACK FRONT FRONT 8436/01/J/05 [Turn over
(IGCSE) Design and Technology May/June 2014 paper 3 variant 2
Question paper found on page 5 / 16 pages total, pdf
.......................................................[2] 8 Fig. 6 shows folding bars. Fig. 6 Add to Fig. 6 to show a piece of sheet metal being bent to shape in the folding bars. © UCLES 2014 0445/32/M/J/14 [3] [Turn over
(A/s) Biology May/June 2010
Examiner report found on page 21 / 72 pages total, pdf
folding and coiling. This question could be used by Centres to encourage candidates to think in a more ordered fashion and to link protein structure and fu nction, in one section of the syllabus, to protein synthesis, which occurs in a different section. (a) (i) This was intended as an easy start to introduce the idea of levels of protein structure, but only about 50% of candidates were able
9705??? Oct/Nov 2019 paper 1 variant 1
Question paper found on page 8 / 12 pages total, pdf
folding barbecue. grill area body folding legs Fig. 7.1 (a) Using notes and sketches, develop a design for the grill area of the barbecue. The design must include a method of adjustment to allow the grill to be set at different heights. [20] (b) Using notes and sketches, develop a design for the folding legs. The design must include methods that allow the legs to be securely
9705??? Oct/Nov 2019 paper 1 variant 3
Question paper found on page 8 / 12 pages total, pdf
folding barbecue. grill area body folding legs Fig. 7.1 (a) Using notes and sketches, develop a design for the grill area of the barbecue. The design must include a method of adjustment to allow the grill to be set at different heights. [20] (b) Using notes and sketches, develop a design for the folding legs. The design must include methods that allow the legs to be securely
9705??? Oct/Nov 2019 paper 1 variant 2
Mark scheme found on page 4 / 17 pages total, pdf
folding (block, folding bars, vice, corner of a bench, folding machine etc.) (0–3) (0–3) Limited tools/equipment 1 mark Good tools/equipment 2 marks Good tools/equipment & safety precautions 3 marks 1(b)(ii) Appropriate method for making part B described Details of appropriate tools, equipment and safety precautions (0–3) (0–3) 6 How to cut out; saw, snips, guillotine,
(A/s) Biology May/June 2016 paper 2 variant 3
Mark scheme found on page 4 / 6 pages total, pdf
folding / coiling, (of polypeptide chain) ; tertiary structure ; (held in position by) ref. to R group interactions ; A two or more bond types in context brings distant, amino acids / parts of the chain, close ; AW [max 3] (ii) water ; A H 2 O [1] [Total: 11] 3 (a) non-self foreign / AW ; A not from the person’
(A/s) Biology May/June 2004 paper 3
Mark scheme found on page 18 / 42 pages total, pdf
folding sites ; hydrogen bonds maintain (secondary structure) ; ref. beta pleated sheet / alpha helix ; ref. folding to form tertiary structure / globular shape ; sulphur bridges / ionic bonds / Van de Waals forces / hydrophobic interactions ; 3 max (b) reverse transcriptase / synthesise DNA from mRNA ; restriction endonuclease / enzyme ; produces sticky ends ; plasmid cut by restriction enzyme ; recombinant DNA formed ; DNA
(A/s) Biology May/June 2004 paper 4
Mark scheme found on page 18 / 42 pages total, pdf
folding sites ; hydrogen bonds maintain (secondary structure) ; ref. beta pleated sheet / alpha helix ; ref. folding to form tertiary structure / globular shape ; sulphur bridges / ionic bonds / Van de Waals forces / hydrophobic interactions ; 3 max (b) reverse transcriptase / synthesise DNA from mRNA ; restriction endonuclease / enzyme ; produces sticky ends ; plasmid cut by restriction enzyme ; recombinant DNA formed ; DNA
(A/s) Biology Feb/March 2019 paper 2 variant 2
Mark scheme found on page 6 / 12 pages total, pdf
folding / coiling, (of polypeptide chain) shown / ref. to 3-D configuration ; globular shape shown ; interactions between, R-groups / side-chains, (of amino acids) not shown ; ref. to any two bond types not shown ; e.g. H bonds / disulfide bridges / ionic bonds / hydrophobic interactions folding allows presence of zinc / AW ; © UCLES 2019 Page 6 of 12
(A/s) Biology May/June 2004 paper 2
Mark scheme found on page 18 / 42 pages total, pdf
folding sites ; hydrogen bonds maintain (secondary structure) ; ref. beta pleated sheet / alpha helix ; ref. folding to form tertiary structure / globular shape ; sulphur bridges / ionic bonds / Van de Waals forces / hydrophobic interactions ; 3 max (b) reverse transcriptase / synthesise DNA from mRNA ; restriction endonuclease / enzyme ; produces sticky ends ; plasmid cut by restriction enzyme ; recombinant DNA formed ; DNA
(A/s) Biology May/June 2004 paper 1
Mark scheme found on page 18 / 42 pages total, pdf
folding sites ; hydrogen bonds maintain (secondary structure) ; ref. beta pleated sheet / alpha helix ; ref. folding to form tertiary structure / globular shape ; sulphur bridges / ionic bonds / Van de Waals forces / hydrophobic interactions ; 3 max (b) reverse transcriptase / synthesise DNA from mRNA ; restriction endonuclease / enzyme ; produces sticky ends ; plasmid cut by restriction enzyme ; recombinant DNA formed ; DNA
(A/s) Biology Feb/March 2022 paper 1 variant 2
Question paper found on page 6 / 20 pages total, pdf
folding of the polypeptidedepends on hydrogen bonding between the side-chains of amino acidsdefines the overall shape and folding of the proteinformed when two or more identical polypeptides join together Bdefines the order of amino acids in the polypeptideusually forms immediately after polypeptide synthesisis held together by all the types of bonding that occur in proteinsfound in globular proteins such as haemoglobin but never in fibrous proteins Cinvolves covalent bonds onlyinvolves interactions between –H and
(IGCSE) Design and Technology May/June 2003 paper 4
Question paper found on page 8 / 20 pages total, pdf
8 For Examiner’s Use (b) Fig. 6 shows a folding stand for an electronic keyboard. Fig. 6 (i) Show how levers and linkages can be used to lock the frame into the open position. [3] 0445/4/M/J/03
(A/s) Biology May/June 2004 paper 5
Mark scheme found on page 18 / 42 pages total, pdf
folding sites ; hydrogen bonds maintain (secondary structure) ; ref. beta pleated sheet / alpha helix ; ref. folding to form tertiary structure / globular shape ; sulphur bridges / ionic bonds / Van de Waals forces / hydrophobic interactions ; 3 max (b) reverse transcriptase / synthesise DNA from mRNA ; restriction endonuclease / enzyme ; produces sticky ends ; plasmid cut by restriction enzyme ; recombinant DNA formed ; DNA
(A/s) Biology May/June 2004 paper 6
Mark scheme found on page 18 / 42 pages total, pdf
folding sites ; hydrogen bonds maintain (secondary structure) ; ref. beta pleated sheet / alpha helix ; ref. folding to form tertiary structure / globular shape ; sulphur bridges / ionic bonds / Van de Waals forces / hydrophobic interactions ; 3 max (b) reverse transcriptase / synthesise DNA from mRNA ; restriction endonuclease / enzyme ; produces sticky ends ; plasmid cut by restriction enzyme ; recombinant DNA formed ; DNA
(A/s) Biology May/June 2008 paper 4
Mark scheme found on page 3 / 9 pages total, pdf
folding / 3D shape ; 2 protein / enzyme, cannot carry out its normal function ; 3 (could be an enzyme) that is essential for a metabolic pathway ; 4 (could) control the expression of another gene / series of genes ; [2 max] (iii) 1 (only) one base / base pair / triplet, needs to change (for teosinte to become maize) ; 2 idea that this could
(A/s) Chemistry May/June 2008 paper 4
Mark scheme found on page 7 / 9 pages total, pdf
a labelled diagram) (award [1] mark for each example) a description of an effect of interchanging amino acids, such as the.. • unfolding of tertiary structure/different folding/different shape (NOT denatured) • inactivity of an enzyme or changing the active site • causing of a protein to become less soluble/coagulate (e.g. sickle cells) 2 x [1] [4] [Total: 13 max 12]
(IGCSE) Design and Technology For examination from 2007 paper 1
Specimen question paper found on page 2 / 8 pages total, pdf
folding seats for this purpose would be very useful. (a) List four points about the function of such seats that you consider to be important. [4] (b) Draw two different types of pivot or sliding mechanism that could be used in the design of the folding seats. [4] (c) Develop and sketch ideas for the seats. (d) Evaluate your ideas and justify why you have chosen one
(A/s) Thinking Skills May/June 2011 paper 1 variant 2
Question paper found on page 4 / 20 pages total, pdf
4 5 Packaging for chocolates is in the form of a prism, as shown below. The prism is made by folding up card from a net. Which one of the nets below will not fold into the prism? A © UCLES 2011 B C 9694/12/M/J/11 D
(A/s) Thinking Skills May/June 2011 paper 1 variant 3
Question paper found on page 17 / 20 pages total, pdf
17 24 Packaging for chocolates is in the form of a prism, as shown below. The prism is made by folding up card from a net. Which one of the nets below will not fold into the prism? A © UCLES 2011 B C 9694/13/M/J/11 D [Turn over
(A/s) Thinking Skills May/June 2011 paper 1 variant 1
Question paper found on page 10 / 20 pages total, pdf
10 15 Packaging for chocolates is in the form of a prism, as shown below. The prism is made by folding up card from a net. Which one of the nets below will not fold into the prism? A © UCLES 2011 B C 9694/11/M/J/11 D
(A/s) Biology Oct/Nov 2011 paper 2 variant 1
Mark scheme found on page 5 / 8 pages total, pdf
folding / AW (v. complex folding) ; A no tertiary structure 6 glycine is repeated every 3rd position / more glycine ; 7 repeating triplets of amino acids / large number repeating amino acid sequences (v. greater variety) ; 8 AVP ; e.g. different primary structure / AW variation in amino acid sequences (v specific sequences) all polypeptides, helical / AW (v. α different to β, polypeptides)
(A/s) Biology Oct/Nov 2015 paper 3 variant 1
Mark scheme found on page 4 / 4 pages total, pdf
folding of leaf ; mp5 feature annotated (cuticle – reduces water loss by evaporation, trichome and folding – reduces diffusion gradient) ; [5] (ii) mp1 at least 4 cells + size at least 40mm + sharp continuous lines ; mp2 4 cells drawn + each cell touching at least 2 of the other cells ; mp3 cell walls drawn as double lines + middle lamella between ; mp4
(IGCSE) Design and Technology Oct/Nov 2004 paper 1
Question paper found on page 8 / 12 pages total, pdf
folding seats for this purpose would be very useful. (a) List four points about the function of such seats that you consider to be important. [4] (b) List or draw four different types of pivot or sliding mechanism that could be used in the design of the folding seats. [4] (c) Develop and sketch ideas for the seats. (d) Evaluate your ideas and justify why you have
(IGCSE) Design and Technology May/June 2014 paper 3 variant 2
Mark scheme found on page 2 / 6 pages total, pdf
1 mm thick mild steel: scriber, odd legs, scribing gauge, scribing block 3 mm thick acrylic: chinagraph pencil, marker pen, felt-tip, leave backing paper on or apply masking tape and use pen or pencil [2] Sheet metal shown between folding bars Folding bars shown in vice Use of mallet or hammer and scrap wood [3] © Cambridge International Examinations 2014 (1) (1) (1)
(IGCSE) Design and Technology May/June 2014 paper 3 variant 1
Mark scheme found on page 2 / 6 pages total, pdf
1 mm thick mild steel: scriber, odd legs, scribing gauge, scribing block 3 mm thick acrylic: chinagraph pencil, marker pen, felt-tip, leave backing paper on or apply masking tape and use pen or pencil [2] Sheet metal shown between folding bars Folding bars shown in vice Use of mallet or hammer and scrap wood [3] © Cambridge International Examinations 2014 (1) (1) (1)
(A/s) Biology Oct/Nov 2011
Examiner report found on page 16 / 78 pages total, pdf
protein, haemoglobin was a globular protein. Although credit was given for a correct statement about collagen, this marking point did require the ‘globular’ description of haemoglobin as candidates had already been told that collagen was a fibrous protein. The best responses gave a clear statement of difference by including features of both molecules. The two other correct responses frequently seen were a comparison with the number of polypeptides in the quaternary structure
(A/s) Biology Oct/Nov 2015 paper 2 variant 3
Mark scheme found on page 6 / 9 pages total, pdf
folding of polypeptide / secondary structure / tertiary structure / active site / catalytic site / binding site ; suggested reasons e.g. electrons less easily transferred ref. to induced fit , more efficient with P ; ora different interactions between polypeptides (in catalase) ; [2] (c) 1 increased, metabolic rate / protein metabolism (after feeding) means, increased / more, hydrogen peroxide (produced) ; 2 idea that less
(A/s) Biology May/June 2006 paper 6
Question paper found on page 6 / 36 pages total, pdf
folding of the mucosa helps the colon to carry out its functions. .............................................................................................................................
(IGCSE) Design and Technology Oct/Nov 2008 paper 4
Question paper found on page 13 / 16 pages total, pdf
Folding [1] (d) The cross-sectional shape of materials is an important feature of structural design. Look at the diagram below and explain why the beam is shaped in this way. ..................................................................................
(A/s) Biology May/June 2010
Examiner report found on page 13 / 72 pages total, pdf
simply stated that they were soluble. Several candidates thought that a globular protein had to have more than one polypeptide chain. Many candidates de scribed the folding of a protein so that hydrophobic R groups are on the inside and hydr ophilic R groups are on the outside of the molecule. Many also stated that a globular protein is spherical or ‘ball-shaped’, which was accepted as an appropriate description. 13
(A/s) Biology Oct/Nov 2011 paper 3 variant 3
Question paper found on page 7 / 16 pages total, pdf
protein digesting enzyme (protease). 1 cm 3 of protein solution clip beads containing protein digesting enzyme (protease) 10 cm 3 of protein solution Fig. 1.3 A student poured 10 cm 3 of a solution containing 100 mg dm –3 of protein into the syringe containing beads. The beads contain protease. At first the clip was fully open and it took 6 seconds to collect a 1.0 cm
(IGCSE) Design and Technology Oct/Nov 2017 paper 2 variant 2
Mark scheme found on page 3 / 4 pages total, pdf
Folding out from the base (star shape). 2 Long strip with triangles folding out from the base or front (not the back). B4(c)(i) Shape [1] Memory [1] Alloy [1] B4(c)(ii) Acceptable answers include: Easy to bend [1] Will return to original shape [1] Safe material [1] [1] + [1] © UCLES 2017 3 Max 2
(IGCSE) Accounting May/June 2011 paper 1 variant 2
Question paper found on page 11 / 16 pages total, pdf
25 20 Folding chair 60 15 18 For Examiner's Use REQUIRED (d) State the basis on which Khalim will value his inventory on 30 April 2011. [3] (e) Calculate the value of Khalim’s inventory at 30 April 2011. Show all your workings. [8] [Total: 23] © UCLES 2011 0452/12/M/J/11 [Turn over
(A/s) Biology May/June 2023 paper 1 variant 3
Question paper found on page 6 / 20 pages total, pdf
protein-digesting enzymes. Replacing one of the amino acids found in the protein with an amino acid that had been synthesised in the laboratory resulted in a modified protein that was not broken down. What could explain why this modified protein was not broken down by the protein-digesting enzymes? A 1The modified protein has a different tertiary structure to the original protein. 2The modified protein is not complementary in shape to
(A/s) Biology May/June 2017
Examiner report found on page 42 / 59 pages total, pdf
protein. (ii) Many candidates deduced that it was the folding of the protein that needed explaining but did not give enough detail. Many wrote neutral statements that the tertiary structure would be affected but did not explain how. A number recognised that a shape change would prevent the binding of the inhibitor but did not say whether it was to the active site or an allosteric site. Only a minority of candidates
(IGCSE) Biology May/June 2017 paper 6 variant 1
Question paper found on page 3 / 12 pages total, pdf
protein in two solutions, A and B, using the results from a set of standard protein solutions. Known concentrations of protein solution were made. Using biuret reagent, the colour intensity score was determined at each concentration. Step 1 Seven test-tubes were labelled 1, 2, 3, 4, 5, 6 and 7. Step 2 Solutions containing different concentrations of protein were made using the volumes of 1% protein solution and
(A/s) Biology May/June 2022 paper 1 variant 1
Question paper found on page 8 / 20 pages total, pdf
protein by a protease enzyme. The student used biuret solution to determine the concentration of protein in the hydrolysis reaction. The student produced a calibration curve using known concentrations of protein. Which diagram shows the calibration curve? A B transmission 0 absorbance 0 0 protein concentration 0 protein concentration C D transmission 0 absorbance 0 0 protein concentration 0 protein concentration 13 A student completed an experiment to measure how increasing concentrations of
(IGCSE) Accounting May/June 2011 paper 1 variant 3
Question paper found on page 11 / 16 pages total, pdf
25 20 Folding chair 60 15 18 For Examiner's Use REQUIRED (d) State the basis on which Khalim will value his inventory on 30 April 2011. [3] (e) Calculate the value of Khalim’s inventory at 30 April 2011. Show all your workings. [8] [Total: 23] © UCLES 2011 0452/13/M/J/11 [Turn over
(IGCSE) Accounting May/June 2011 paper 1 variant 1
Question paper found on page 11 / 16 pages total, pdf
25 20 Folding chair 60 15 18 For Examiner's Use REQUIRED (d) State the basis on which Khalim will value his inventory on 30 April 2011. [3] (e) Calculate the value of Khalim’s inventory at 30 April 2011. Show all your workings. [8] [Total: 23] © UCLES 2011 0452/11/M/J/11 [Turn over
(A/s) Biology May/June 2023 paper 3 variant 4
Question paper found on page 2 / 16 pages total, pdf
protein, using the milk containing a 5.0% concentration of protein, M. You will need to carry out a serial dilution of the milk containing 5% protein, M, to reduce the concentration of protein by half between each successive dilution. You will need to prepare four concentrations of protein in addition to 5.0% protein, M. After the serial dilution is completed, you will need to have 10 cm
(IGCSE) Biology May/June 2017 paper 4 variant 2
Mark scheme found on page 4 / 11 pages total, pdf
protein) / AW ; (protein synthesis) uses energy ; order of amino acids determined by base sequence of, mRNA / DNA / gene ; active transport ; 1 1 2 3 4 5 3 6 protein uses, energy / ATP (from respiration) ; idea of protein interaction with ions ; (to) change shape of protein ; ions move through the protein ; against concentration gradient / lower concentration to high concentration
(A/s) Biology May/June 2018 paper 2 variant 2
Mark scheme found on page 10 / 18 pages total, pdf
protein ; A pore protein / has a pore / has a channel 2 channel / pore, can form from polypeptides or (protein) has quaternary structure ; 3 hydrophilic R-groups, on amino acids lining channel / face inwards (towards channel) ; A hydrophilic, lining / channel A water-filled, channel / AW A idea that passage is through hydrophilic region of protein 4 allows facilitated diffusion ; 5 increases permeability
(A/s) Biology May/June 2005 paper 1
Question paper found on page 5 / 20 pages total, pdf
protein which consists entirely of repeating residues of one amino acid. increasing symmetry 024681012 14 random coil α -helix pH Which statement is true? A At pH2 the protein has lost its secondary structure. B At pH2 the protein has lost its tertiary structure. C At pH10 the protein has lost its primary structure. D At pH10 the protein has lost its secondary structure.
(IGCSE) Design and Technology Oct/Nov 2017 paper 1 variant 2
Mark scheme found on page 2 / 3 pages total, pdf
folding features – hinged frames, sliding tubes, tubes located in fittings, support struts, detachable legs/top, nuts/bolts, different types of hinge. AOVR 2 × 2 4 Question Answer 2(a) Accept any four additional suitable points – methods of construction, suggested sizes, suitable colour, visual impact, advertising aspects, use of net, printing methods, folding issues. AOVR 1 × 4 4 2(b) Accept drawings of any
(IGCSE) Biology May/June 2018 paper 5 variant 1
Question paper found on page 5 / 12 pages total, pdf
protein in milk into a white solid, protease enzymes can be used to digest the protein. The digested protein forms a colourless liquid. A hypothesis stated: The optimum temperature for protease enzymes to digest changed milk protein is 37 °C. Describe a method that could be used to test this hypothesis. Do not carry out this investigation. ...........................
(IGCSE) Design and Technology May/June 2018 paper 4 variant 1
Question paper found on page 8 / 20 pages total, pdf
folding clothes airer in the assembled position. Fig 8a (i) Fig. 8b Name the strengthening feature on the clothes airer shown in Fig. 8b. .............................................................................................
(A/s) Biology Oct/Nov 2018 paper 1 variant 3
Question paper found on page 7 / 20 pages total, pdf
protein-digesting enzymes. Replacing one of the amino acids found in the protein with one that had been synthesised in the laboratory resulted in a modified protein that was not broken down. What could explain why this modified protein was not broken down by the protein digesting enzymes? A 1 The modified protein has a different tertiary structure to the original protein. 2 The modified protein is not complementary in shape to the
(IGCSE) Design and Technology May/June 2018 paper 4 variant 3
Question paper found on page 8 / 20 pages total, pdf
folding clothes airer in the assembled position. Fig 8a (i) Fig. 8b Name the strengthening feature on the clothes airer shown in Fig. 8b. .............................................................................................
(A/s) Biology Feb/March 2016 paper 3 variant 3
Question paper found on page 4 / 12 pages total, pdf
protein solution you will use. Decide which concentrations of protein solution to prepare using simple dilution of the 1.0% protein solution, P . Complete Table 1.1 to show how you will prepare the other concentrations. Table 1.1 volume of 1.0% protein solution, P / cm 3 volume of distilled water, W / cm 3 percentage concentration of protein solution 5 0 0 5 1.0 0.0 [
(A/s) Chemistry May/June 2004 paper 3
Mark scheme found on page 33 / 41 pages total, pdf
protein peripheral protein (1) channel protein allows passage of solutes (1) Protein increases the flexibility of the bilayer (1) van der Waals’ forces between the alkyl groups of phospholipids (1) ionic and H-bonds between phosphate residues / protein and the aqueous cell fluid (1) [6] CH 2 – O – CO – R | CH – O – CO – R | O | || CH 2
(A/s) Biology Feb/March 2016 paper 3 variant 3
Mark scheme found on page 3 / 4 pages total, pdf
protein ; 2 volumes of P for three percentage concentrations of protein ; 3 volumes of P and W for three percentage concentrations of protein make 5 cm 3 ; [3] (ii) volume of, sample / protein solution, to test or volume of reagents (potassium hydroxide solution / K and copper sulfate solution / C ) ; [1] (iii) 1 table drawn + heading for percentage concentration of protein ;
(A/s) Biology Oct/Nov 2012 paper 2 variant 2
Mark scheme found on page 5 / 9 pages total, pdf
protein drawn and labelled as protein; treat description as neutral 5 protein type qualified; e.g. if protein is labelled as integral / intrinsic must extend into hydrophobic core and be in phosphate head portion transmembrane / transport / carrier / must extend across / through bilayer if channel protein must channel / pore show channel peripheral / extrinsic must be on surface / on one side aquaporin gated protein 6 cholesterol, labelled;
(IGCSE) Biology May/June 2017 paper 5 variant 1
Mark scheme found on page 4 / 8 pages total, pdf
protein / no protein / AW ; 2 to compare with tubes containing protein / to show the effect is due to protein / to show the colour when protein is present ; 1(b)(ii) May/June 2017 Cambridge IGCSE – Mark Scheme PUBLISHED idea that it is a qualitative method / not quantitative / not measured ; 2 subjective / judged by eye / could be visually impaired ; similar concentrations
(IGCSE) Design and Technology Oct/Nov 2017 paper 3 variant 2
Question paper found on page 8 / 20 pages total, pdf
notes to show how both end frames could be locked against the table top to prevent them from folding inwards when in use. [4] (e) Use sketches and notes to show a modification to the end frames so that the picnic table could remain level when positioned on uneven ground. Include details of materials, fittings and constructions. [5] © UCLES 2017 0445/32/O/N/17
(IGCSE) Design and Technology Oct/Nov 2008 paper 4
Mark scheme found on page 5 / 6 pages total, pdf
(1). [2] 13 (a) Compression ~ top of beam (1) Tension ~ bottom of beam (1) [2] (b) As symmetrical R L = R R (1) = 50N (1) (c) Name [2] Diagram Use Ribs Plastics packaging Lamination/Sandwich [1] Display board Triangulation Roof truss [1] [1] [1] Folding Cardboard packaging [1] © UCLES 2008
(IGCSE) Design and Technology May/June 2019 paper 4 variant 2
Question paper found on page 7 / 20 pages total, pdf
folding aluminium work platform used for building work or decorating. Fig. 6 (i) The platform is designed to take stationary and moving loads. Explain, using examples, what is meant by each type of load. ..........................................................................
(A/s) Biology May/June 2019 paper 3 variant 5
Question paper found on page 3 / 16 pages total, pdf
protein in blood plasma can be measured to identify possible health problems. In this investigation you will be using protein solutions, P and U, instead of blood plasma. You will need to: • • • • prepare a serial dilution of solution P carry out the test for protein on each concentration of protein solution carry out the test for protein on the unknown concentration of protein, U estimate the concentration of
(A/s) Biology Oct/Nov 2021 paper 3 variant 1
Question paper found on page 6 / 16 pages total, pdf
protein concentrations used in this investigation. The position for 1.0% and 0.0% are shown on the scale. 0.0% protein concentration Fig. 1.2 Complete the scale in Fig. 1.2 by showing the positions of the protein concentrations you prepared in step 1. [1] (vi) Use your results in (a)(ii) and (a)(iv) to estimate the protein concentration of U. Show your
(A/s) Biology May/June 2010 paper 2 variant 2
Mark scheme found on page 5 / 7 pages total, pdf
folding coiling ; 2 interactions between, R groups side chains ; 3 two correctly named bonds ; e.g. hydrogen bonds, disulfide, bonds/bridges, ionic bonds, hydrophobic interactions 4 further description of bonds ; e.g. disulfide between cysteine (S–H) groups hydrogen between polar groups (NH– and CO–) ionic between ionised amine and carboxylic acid groups hydrophobic interactions between non-polar side chains 5 ref. active site,
(A/s) Biology May/June 2004
Examiner report found on page 8 / 20 pages total, pdf
1 (a) Candidates were well aware of the bonds involved and scored two marks but few were able to link the bonds to the various stages of globular protein structure. Very few had any idea of alpha helix and beta pleated sheets. Few candidates mentioned the fact that the amino acid sequence determines the folding sites of the protein. Some candidates referred to a quater nary structure rather than the tertiary structure.
(A/s) Biology Feb/March 2016 paper 3 variant 3
Question paper found on page 2 / 12 pages total, pdf
protein in a person’s urine may be measured to identify certain health problems. You are required to: • prepare different concentrations of the protein solution, P • standardise and carry out the tests for protein concentration • record the results of tests for the known concentrations of protein and an unknown sample, U • estimate the concentration of protein in U . The protein concentration can be measured by using potassium hydroxide
(IGCSE) Biology May/June 2014 paper 2 variant 3
Question paper found on page 11 / 20 pages total, pdf
protein sugar 37% Fig. 5.1 Use the data in Fig. 5.1 to calculate the percentage of protein present in the milk solids. Show your working. % protein in the milk solids ...........................................................[2] (d) Enzymes are used to break down