TJC 2023 H2 Prelim P4 ANS_Sharing

1 [TURN OVER TEMASEK JUNIOR COLLEGE 2023 JC2 PRELIMINARY EXAMINATION Higher 2 CANDIDATE NAME CENTRE NUMBER S INDEX NUMBER BIOLOGY 9744/04 Paper 4 Practical 30 August 2023 2 hour 30 minutes Candidates answer on the Question Paper. Additional Materials: As listed in the Confidential Instructions. READ THESE INSTRUCTIONS FIRST Write your name, CG, Centre number, index 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 staples, paper clips, glue or correction fluid. This document consists of 16 printed pages. Shift Laboratory For Examiner’s Use 1 / 17 2 / 17 3 / 21 Total / 55 Answer all questions in the spaces provided on the Question Paper. The use of an approved scientific calculator is expected, where appropriate. You may lose marks if you do not show your work or if you do no use appropriate units. 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.

2 Answer all questions. 1 (a) You will investigate the effect of different temperatures on the permeability of the cell surface membrane of beetroot cells. Beetroot is a vegetable that contains a red pigment in its cells. When beetroot tissue is put into water, the red pigment can move out of the cells through the cell surface membrane, changing the water to a red colour. You are provided with: labelled contents hazard volume / cm 3 B 4 pieces of beetroot none - W distilled water none 100.0 The red pigment in beetroot cells can stain clothing and skin. Use blunt forceps to handle beetroot tissue and, if any pigment comes into contact with your skin, wash it off immediately under cold water. It is recommended that you wear suitable eye protection. You will need to:  put beetroot tissue in water at different temperatures  leave the beetroot tissue in the water for a period of time  record the intensity of colour in the water at each temperature. (i) The temperature range that you will use must include a minimum temperature of 25˚C and a maximum temperature of 65˚C. State other temperatures that you will use in your investigation. [1] 35˚C, 45˚C, 55˚C  Must have at least 3 other temperatures between the range  Must have regular intervals Read step 1 to step 13 before proceeding. Proceed as follows. 1 Cut the beetroot pieces into 2 mm thick discs. You will need at least 25 discs. 2 Put all the discs that you have cut into the beaker labelled D and cover them with approximately 30 cm3 distilled water, W. 3 Stir with a glass rod. 4 Pour off the water into the beaker labelled For waste, leaving the discs in th