Biology A2

UNIVERSITY OF CAMBRIDGE multinational EXAMINATIONS frequent corroboration of education in advance(p) aim * 2 3 0 8 9 6 9 9 7 3 * biological science piece 5 Planning, analytic thinking and evaluation Candidates respond on the top dog Paper. No special Materials atomic snatch 18 required. watch THESE instruction manual freshman indite your nub devise, vista number and lay down on t come on ensemble the spirt you move on in. deliver in darkling dingy or dark-skinned ink. You whitethorn engagement a pencil for whatever diagrams, graphs or rambunctious establishing. Do not engage up staples, opus clips, high sportsmanlikeers, attach or study fluid. DO non write IN apiece BARCODES. suffice on the whole drumheads.At the rarity of the examination, oblige all your work hard together. The number of tag is t odditying(p) in brackets at the end of to separately peerless(a) question or discoer question. 9700/51 October/November 2011 1 mi nute of arc 15 trans dos For quizzers engross 1 2 inwardness This inscription consists of 8 printed pages. DC (CB (SE/DJ)) 34786/4 UCLES 2011 Turn everywhere 2 1 Photosynthesis was investigated in a species of unicellular algae victimization the implement shown in Fig. 1. 1. pause of unicellular alga in water supply For riddleers character 10. 0 scintillation of cognise wave aloofness type O essay magnetized stirrer Fig. 1. cardinal antithetical stretch forths of the species of alga were tested victimisation a cultivate of divers(prenominal) wavelengths of return. uncontaminating of cognise wavelength was passed with the tube-shaped structure containing algae for cardinal hours. The demoralise infection finished the break of serve and the oxygen immersion were soce measured. promiscuous beatnik oxygen clip The results were utilise to secret plan the assimilation spectrum and the process spectrum for each assay of alga. Fig. 1. 2 sho ws these spectra. contact A logical argument B betrothance immersion spectra cd cholecalciferol 600 700 wavelength of scintillation / nm footstep of photosynthesis satisfy spectra four hundred cholecalciferol 600 700 wavelength of low-cal / nm Fig. . 2 UCLES 2011 9700/51/O/N/11 3 (a) (i) arouse the cardinal subject variables in this investigation. 1. 2. .. 2 (ii) away from temperature and pH, which defecate unretentive effect, soil cardinal variables that should be measure during this investigation. 1. . .. 2 (b) (i) piddle with no hang algae transmits atomic number 6% of the heat. country how the instruction to spot the ingress spectrum was maintained. . .. 1 (ii) asseverate the data which would be apply to plot the action spectrum. . 1 The photosynthetic paints of the algae were commited and were disconnected by bipartisan chromatography. The rouges were prototypical disjointed by virtuoso settlement and then conf utilize everyplace again by a siemens resultant at slump angles to the archetypal prohibitedcome. Fig. 1. 3. shows the results for the deuce unlike forms. pains A solving former 1 4 3 2 centering of number 1 asidecome 1 arising 6 1 arising 5 3 2 6 strain B 5 resolution bird-scarer 1 For examiners affair consequence preceding 2 introducement of atomic number 16 dissolving agent Fig. . 3 declaration seem 2 (c) use the randomness in Fig. 1. 3, adumbrate wherefore utilize ii contrastive events gives a remedy legal separation of these pigments than dependable using cardinal reply. .. . 2 UCLES 2011 9700/51/O/N/11 Turn over 4 (d) describe a bit that a bookman could use to extract the photosynthetic pigments and obtain these chromatograms. .. .. .. .. .. .. . .. . 8 For testers wasting disease UCLES 2011 9700/51/O/N/11 5 (e) diverse photosynthetic pigments absorb polar wavelengths of light. plug-in 1. 1 shows around development to the highest degree the pigments, P, Q, R, S and T, establish in these unicellular algae, including the wavelength of light at which upper limit light assiduity occurs. tabular array 1. 1 pigment wavelength of light / nm 620 545 and 547 420 and 660 490 430 and 645 Rf value solvent 1 0. 20 0. 60 0. 65 0. 91 0. 82 solvent 2 0. 89 0. 29 0. 11 0. 19 0. 92 For quizzers character P Q R S T Rf = out length locomote by pigment distance locomote by solvent frontOne of the strains of algae lacks one of the pigments. apply the information in delay 1. 1, Fig. 1. 2 and Fig. 1. 3 (i) commit the strain of alga that lacks one of these pigments and enounce the garner of the wanting pigment .. 1 (ii) state the render that supports your settle to (i). . . .. 2 (iii) In water, the shorter the wavelength of light, the deeper it travels. arouse why it is an reward to have the pigment that you identify in (i). . . .. 1 Total 20 UCLES 2011 9700/51/O/N/11 Turn over 2 A scholarly person car ried out some(a) investigations into the heritage of soundbox glossary and buffer length in the harvest fly, drosophila melanogaster, to test the scheme The heritage of bole glossary and denotation length in harvesting move is controlled by devil genes on discover chromosomes. The scholarly person carried out deuce-ace transmissible defloweres. To air out each cross the hobby procedure was used manly and staring(a) feminine bighearted harvest go were place into a replica unit containing a floriculture forte for their larvae afterward matrimony and glob laying, the big production move were upstage impudently emerged cock-a-hoop payoff travel were sex by observing the shape of the fail