2024 EJC Prelim Biology P4 (A)

© EJC 2024 9744/04/J2H2PRELIM/2024 EUNOIA JUNIOR COLLEGE JC2 Preliminary Examinations 2024 General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME ANSWERS CIVICS GROUP 2 3 - REGISTRATION NUMBER BIOLOGY Paper 4 Practical 9744/04 22 August 2024 2 hours 30 minutes Candidates answer on the Question Paper. READ THESE INSTRUCTIONS FIRST Write your name, civics group and registration number on all the work you hand in. Give details of the practical shift and laboratory, where appropriate, in the boxes provided. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use stapler, paper clips, highlighters, glue or correction fluid/tape. This document consists of 22 printed pages and 2 blank pages. For Examiner’s Use 1 2 3 Total 55 Answer all questions in the spaces provided in the Question Paper. The use of an approved scientific calculator is expected, where appropriate. You may lose marks if you do not show your working or if you do not use appropriate units. The number of marks is given in brackets [ ] at the end of each question or part question. Shift Laboratory

© EJC 2024 9744/04/J2H2PRELIM/2024 2 Answer all questions. 1 You will be investigating the effect of salt concentration on the movement of water in potatoes. You are provided with the materials shown in Table 1.1. Table 1.1 labelled contents hazard volume / cm3 P 5 lengths of potato none – W distilled water none 150 S 1 mol dm–3 salt solution none 150 It is recommended that you wear suitable eye protection. (a) You will need to make different concentrations of salt solution using simple dilution of the 1.00 mol dm–3 salt solution, S. You will need to prepare 40 cm3 of each concentration. Table 1.2 shows two of the concentrations you will use. Decide which other concentrations of salt solution you will use. (i) Complete Table 1.2 to show how you will prepare the other concentrations. Table 1.2 final concentration of salt solution / mol dm–3 volume of S / cm3 volume of distilled water, W / cm3 1.00 0.75 0.50 0.25 0.00 40 30 20 10 0 0 10 20 30 40 [2] 1. At least 3 more concentrations (evenly spaced) (A: 4, e.g. 0.80, 0.60, 0.40, 0.20) and 2 d.p. 2. All volumes of S and W add up to 40 NOTE: In the event that you come across the term “proportional dilution”, you can assume that it is referring to “simple dilution”. In addition, doing serial dilution will not give you a 0.00 with 5 concentrations.

© EJC 2024 9744/04/J2H2PRELIM/2024 3 [Turn over Carry out step 1 to step 11. step 1 Prepare the concentrations of salt solution, as shown in Table 1.2, in the beakers provided. step 2 Cut 10 discs of potato for each of the concentrations prepared in st