2026 EJC JC2 H2 Biology Prelims P4 (Q)

© EJC 2026 9477/04/J2H2PRELIM/2026 EUNOIA JUNIOR COLLEGE JC2 Preliminary Examinations 2026 General Certificate of Education Advanced Level Higher 2 CANDIDATE NAME CIVICS GROUP 2 5 - REGISTRATION NUMBER BIOLOGY Paper 4 Practical 9477/04 25 August 2026 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 17 printed pages and 3 blank pages. For Examiner’s Use 1 2 3 Total 50 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

2 © EJC 2026 9477/04/J2H2PRELIM/2026 BLANK PAGE

3 © EJC 2026 9477/04/J2H2PRELIM/2026 [Turn over Answer all questions. 1 During the manufacture of a fruit juice, an unwanted colour can sometimes appear in the juice. An enzyme can be used to remove this colour. You will carry out an investigation to determine the concentration of enzyme that is most effective at removing the colour in mock fruit juice, J. Solution J is not real fruit juice, so is not safe to drink. You are provided with the materials shown in Table 1.1. Table 1.1 labelled contents hazard volume / cm3 E 2.0% enzyme solution harmful irritant 25 J mock fruit juice harmful 60 W distilled water none 100 If any solution comes into contact with your skin, wash off immediately under cold water. It is recommended that you wear suitable eye protection. (a) You will need to carry out a serial dilution of the 2.0% enzyme solution, E, to reduce the concentration by half between each successive dilution. In addition to the 2.0% enzyme solution, E, you will need to prepare five other concentrations of enzyme solution, including one control. After the serial dilution is completed, you need to have at least 10 cm3 of each concentration available to use. (i) Using a table, show how the five other concentrations of enzyme solution can be made. [3] (ii) Describe the control. ……………………………………………………………………………………………………… …………………………………………………………………………………………………… [1]

4 © EJC 2026 9477/04/J2H2PRELIM/2026 Carry out step 1 to step 11. 1. Prepare the concentrations of enzyme solution, as decided in (a)(i), in the vials provided. 2. Label the test-tubes with the six concentrations of enzyme solution. 3. Put 5 cm3 of J into each test-tube. 4. Using the beaker labelled hot water, collect approximately 200 cm3 of hot water from where it is provided in the laboratory. Using the beaker labelled tap water, collect approximately 200 cm 3 of tap water from the sink. 5. Set up a water-bath with water at approximately 40 °C. Maintain the water-bath at approximately 40 °C during step 6 to step 9. 6. Put the test-tubes from step 3 into the water-bath. Leave the test-tubes for 3 minutes. 7. Put 5 cm3 of the 2.0% enzyme solution into the appropriately labelled test-tube. Shake gently to mix. 8. Repeat step 6 with the other concentrations of enzyme solution you prepared in step 1. 9. Start timing and leave the test-tubes in the water-bath for 10 minutes. While you are waiting, carry on with the rest of Question 1. 10. After 10 minutes (step 9), remove the test-tubes from the water-bath. Observe the colour of the solution in each test-tube. To see the colour more clearly, it may help to hold a white tile behind the test-tube. You may see the same colour in more than one test-tube. 11. Record your results in (a)(iii) using the symbols shown in Table 1.2. Table 1.2

5 © EJC 2026 9477/04/J2H2PRELIM/2026 [Turn over (iii) Record your results in an appropriate table. You may use the same symbol for more than one test-tube. [3] (iv) Using your results in (a)(iii), state which concentration (s) of enzyme removed the colour most effectively. …………………………………………………………………………………………………... [1] (v) Using your knowledge of enzymes, explain the trend in your results. ……………………………………………………………………………………………………… ……………………………………………………………………………………………………… ……………………………………………………………………………………………………… …………………………………………………………………………………………………... [2] (vi) State one variable, other than temperature, that needs to be controlled in this investigation. …………………………………………………………………………………………………... [1]

6 © EJC 2026 9477/04/J2H2PRELIM/2026 (vii) The procedure used in this investigation has several sources of error. Table 1.3 shows one of these sources. Complete Table 1.3 by: • stating one other source of error • describing an improvement to the procedure for each of the two sources of error. Table 1.3 source of error how to improve the procedure the test-tube with 2.0% enzyme was left for longer than the other test-tubes [2] (b) Grapes are a type of fruit that can be eaten freshly picked or dried. Table 1.4 shows the sugar content of fresh grapes and dried grapes. Table 1.4 type of sugar sugar content/g per 100g of grapes fresh dried glucose 6.5 27.0 fructose 7.5 29.5 sucrose 0.5 1.0

7 © EJC 2026 9477/04/J2H2PRELIM/2026 [Turn over (i) Use the grid provided to plot a bar chart of the data in Table 1.4. [4]

8 © EJC 2026 9477/04/J2H2PRELIM/2026 (ii) The concentration of all sugars in dried grapes is higher than in fresh grapes. Calculate the percentage increase in the concentration of glucose in dried grapes. Show your working clearly. answer = ……………………………………. % [2] (iii) Suggest why the glucose concentration is higher in the dried grapes than in the fresh grapes. ……………………………………………………………………………………………………… …………………………………………………………………………………………………… [1] [Total: 20]

9 © EJC 2026 9477/04/J2H2PRELIM/2026 [Turn over BLANK PAGE

10 © EJC 2026 9477/04/J2H2PRELIM/2026 2 Some students observed a flowering plant and noticed that the flower was supported by a long stalk. To investigate how the stalk supported the flower, the students cut out a piece of stalk that was 40 mm long and then split this lengthways into 4 strips, as shown in Fig. 2.1. Fig. 2.1 The students observed that the strips immediately curved lengthways so that the epidermis was on the inside of the curve. All the strips were put into a Petri dish containing water and left for a period of time. After soaking in water, the strips curved even further. Fig. 2.2 shows the appearance of a strip after being soaked in water, viewed from one end. Fig. 2.2 In an investigation to find the water potential of the tissues in the flower stalk, the students decided to: • put strips in different concentrations of sucrose solution • observe the direction and degree of curvature of the strips • measure the angle of curvature of the strips using a transparent protractor, ruler, marker and white tile