Cambridge A Level Biology 9700 — 2006 May/June Paper 3 · Variant 1

This document consists of 6 printed pages and 2 blank pages. SP (SC/CGW) T10863/3 © UCLES 2006 [Turn over UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certificate of Education Advanced Subsidiary Level and Advanced Level BIOLOGY 9700/03 Paper 3 Practical Test AS May/June 2006 1 hour 15 minutes Candidates answer on the Question Paper. Additional Materials: As listed in the Instructions to Supervisors. READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. You are advised to spend 40 minutes on Question 1 and 35 minutes on Question 2. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. Centre Number Candidate Number Name For Examiner’s Use 1 2 TOTAL

2 9700/03/M/J/06 For Examiner’s Use © UCLES 2006 1 You are required to carry out an investigation into the relative quantities of reducing sugar in potato and onion tissue. You are provided with test-tubes, labelled X, Y and Z, each containing a different concentration of reducing sugar. You are also provided with some potato tissue, labelled P, and some onion tissue, labelled O. (a) Carry out the test for reducing sugars on samples X, Y and Z. (i) Describe, giving full practical details, how you carried out the test for reducing sugars. … … … … …[2] (ii) Record your observations in Table 1.1. (iii) Complete the column headed conclusion. Retain the test-tubes for comparison with the results you obtain in (b)(ii). Table 1.1 solution observation conclusion X … … … … Y … … … … Z … … … … [3]

3 9700/03/M/J/06 [Turn over For Examiner’s Use © UCLES 2006 (iv) Determine the order of concentration of reducing sugar in the three solutions and complete Table 1.2. Table 1.2 concentration X or Y or Z high medium low [1] (b) Finely cut up tissue P on the tile and place the crushed tissue into one of the two empty test-tubes provided. Add 2 cm3 of water to the test-tube. Place a bung in the open end of the test-tube and shake gently. Repeat the process for tissue O using the other empty test-tube. (i) Carry out the test for reducing sugars on both samples. Record your observations in Table 1.3. Table 1.3 tissue sample observation P … … O … … [2] (ii) Compare your observations with the results obtained for part (a). … … … … …[2]

4 9700/03/M/J/06 For Examiner’s Use © UCLES 2006 (c) Explain how you made sure that your tests produced a fair comparison. … … … … …[3] [Total : 13]

5 9700/03/M/J/06 [Turn over For Examiner’s Use © UCLES 2006 2 S1 is a slide of a stained transverse section of an artery. (a) (i) Make a large, labelled, plan diagram to show the distribution of the tissues. [4] (ii) Calculate the magnification of your drawing. Show your working. magnification ……………………… [2]

6 9700/03/M/J/06 For Examiner’s Use © UCLES 2006 (b) Fig. 2.1 is a photomicrograph of an artery and a vein. Fig. 2.1 Describe three visible differences between the artery and the vein. Explain the reason for each structural difference. difference 1 … explanation … … difference 2 … explanation … … difference 3 … explanation … …[6] [Total : 12]

8 9700/03/M/J/06 BLANK PAGE Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity. University of Cambridge International Examinations is part of the University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS GCE Advanced Level and GCE Advanced Subsidiary Level MARK SCHEME for the May/June 2006 question paper 9700 BIOLOGY 9700/03 Paper 3 Maximum raw mark 25 This mark scheme is published as an aid to teachers and students, to indicate the requirements of the examination. It shows the basis on which Examiners were initially instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began. Any substantial changes to the mark scheme that arose from these discussions will be recorded in the published Report on the Examination. All Examiners are instructed that alternative correct answers and unexpected approaches in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills demonstrated. Mark schemes must be read in conjunction with the question papers and the Report on the Examination. The minimum marks in these components needed for various grades were previously published with these mark schemes, but are now instead included in the Report on the Examination for this session. • CIE will not enter into discussion or correspondence in connection with these mark schemes. CIE is publishing the mark schemes for the May/June 2006 question papers for most IGCSE and GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses.

Page 1 Mark Scheme Syllabus Paper GCE A/AS Level – May/June 2006 9700 03 © University of Cambridge International Examinations 2006 Question Expected Answers Marks Additional Guidance 1 (a) (i) Equal volume test solution and Benedits/excess Benedicts; Boil/heat in water bath above 80 °C; 1 1 Reject direct heat (ii) & (iii) X lowest sugar conc e.g. green/blue green/blue with hint of yellow; Y highest sugar conc e.g. red; Z medium sugar conc e.g. yellow orange/brown; 1 1 1 Observation and conclusion must both be correct (iv) Y top Z middle and X bottom; 1 (b) (i) P no or little sugarIblue/green/yellow; Q more sugar than P/green/yellow/ brown; 1 1 Accept answers with P similar to Q as old potatoes may contain sugars (ii) P closest to X or Z with explanation: Q closest to Y or Z with explanation; 1 1 (c) Three from: Same volumes of solutions/reagents; Same volumes of tissue; Heat for same time; Method for comparing colours; Same temperature of water bath; Replication; max 3 Total 13 2 (a) (i) Quality of drawing; Crinkled inner lining; Ratio of wall to lumen between 1:4 − 1:8; Correct label; 1 1 1 1 Slide is TS rat aorta (ii) Correct mag (actual size 1 mm) ± 10%; Measure specimen and measure drawing; Divide drawing by specimen; max 2 (b) Artery thick wall; Withstand pressure/muscular; Vein larger lumen; To ease blood flow; Artery more round in shape; Vein lacks muscles/support structures; 1 1 1 1 1 1 Either way round Accept artery has crinkles inner surface to allow expansion even though not visible in pm. Total 12 Total 25