TKGS 2024 S4 Prelim Bio Paper 2

TANJONG KATONG GIRLS’ SCHOOL PRELIMINARY EXAMINATION SECONDARY FOUR EXPRESS CANDIDATE NAME CLASS 4 INDEX NUMBER BIOLOGY 6093/02 Paper 2 13 August 2024 1 hour 45 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name, class and register number on all the work you hand in. Write in dark blue or black pen. You may use a HB pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided. Section B Answer one question. Write your answers in the spaces provided. The use of an approved scientific calculator is expected, where appropriate. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use Section A Setter : Mr Lim Kok Siong Markers : Mr Lim Kok Siong, Mrs Tan-Wong Woei Ling Section B Total / 80 This document consists of 22 printed pages.

2 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 Section A Answer all questions. 1 Fig. 1.1 and Fig. 1.2 show the sections of alveoli and a villus respectively. Fig. 1.1 Fig. 1.2 (a) With reference to Fig. 1.1, describe one adaptation of an alveolus with respect to its function. …………………………………………………………………………………….…………… …………………………………………………………………………………….…………[1] (b) Cell A contains numerous small finger-like projections from the cell membrane. Name these projections. …………………………………………………………………………………….…………[1] (c) Structure B absorbs nutrients from the lumen of the small intestine. Name structure B. …………………………………………………………………………………….…………[1] (d) Name the substances that are absorbed into the blood capillaries of the alveoli and the villi. blood capillaries of the alveoli: ……………………………………………………………... blood capillaries of the villi: ……………………………………………………………….[2] [Total: 5] epithelial cells of alveoli blood capillary red blood cell blood capillaries cell A B

3 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 2 Fig. 2.1 shows a section of a mammalian heart. Fig. 2.1 (a) Describe one structural difference in the walls of vessels A and B. …………………………………………………………………………………………………. ……………………………………………………………………………………….………[1] (b) On Fig. 2.1, draw arrows to show the flow of blood inside the heart. [1] (c) Name valve X and explain its significance during ventricular systole. …………………………………………………………………………………………………. …………………………………………………………………………………………………. ……………………………………………………………………………………….………[2] A B valve X

4 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 (d) Table 2.1 shows the cardiac cycle of a healthy man at rest. Table 2.1 time / s at rest during exercise atrium ventricle atrium ventricle 0.0 – 0.1 legend: 0.1 – 0.2 contraction 0.2 – 0.3 0.3 – 0.4 relaxation 0.4 – 0.5 0.5 – 0.6 0.6 – 0.7 0.7 – 0.8 0.8 – 0.9 0.9 – 1.0 1.0 – 1.1 1.1 – 1.2 (i) Calculate the heart rate of the man at rest. Show your workings clearly. heart rate: ……………………. beats / minute [1] (ii) In Table 2.1, shade the relevant boxes to suggest how the cardiac cycle of the man will be like during vigorous exercise. [1] [Total: 6]

5 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 3 (a) Fig. 3.1 shows a nephron and the blood capillary surrounding it. Fig. 3.1 (i) Name structures A and B. A: ………………………………………….. B: ………………………………………….. [2] (ii) Some substances in A are forced out into the Bowman’s capsule of the nephron. Explain how these substances are forced into the Bowman’s capsule. ………………………………………………………………………………………….. ………………………………………………………………………………………….. ………………………………………………………………………………………..[2] blood capillary A B Bowman’s capsule

6 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 (b) Fig. 3.2 shows a type of dialysis where the dialysis fluid enters the abdominal cavity. Exchange of materials will take place across the membrane that surrounds the abdominal cavity. This removes the waste products from the blood. After a few hours, the used fluid is drained out of the cavity, and fresh fluid will re -enter the abdominal cavity. Fig. 3.2 Suggest why the fluid must be changed after a few hours. …………………………………………………………………………………………………. …………………………………………………………………………………………………. ……………………………………………………………………………………….………[2] [Total: 6] abdominal cavity fluid membrane surrounding the abdominal cavity

7 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 4 Fig. 4.1 shows a submerged aquatic plant known as bladderwort. Bladderworts thrive in aquatic environments that are poor in nutrients. To ensure their optimal development, they have evolved to be carnivorous in nature. The outer cells around the entrances of the bladders of the plant secrete a sticky mucus, which traps and then digests small water animals such as water fleas. Fig. 4.1 (a) Write the chemical equation of the process that allows bladderwort s to obtain carbohydrates. [2] (b) Name the elements of the carbohydrates formed in (a). …………………………………………………………………………………….…………[1] (c) The nutrients obtain from the digestion of the water fleas enable bladderwort s to develop optimally in the aquatic environment. Suggest how the digestion of water fleas ensures the optimal development of bladderworts. …………………………………………………………………………………….…………… …………………………………………………………………………………….…………… …………………………………………………………………………………….…………[2] [Total: 5] bladder water flea undergoing digestion water flea green leaves bladder entrance

8 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 5 Fig. 5.1 shows a setup to investigate transpiration of a plant. Fig. 5.1 The setup was placed under different environmental conditions. Table 5.1 shows the data collected. Table 5.1 environment condition air movement temperature / °C humidity / % rate of transpiration / gh-1 A still air 30.0 65.0 9.8 B still air 30.0 80.0 4.7 (a) Account for the difference in transpiration rates between environment conditions A and B. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………………. …………………………………………………………………………………………………. ………………………………………………………………………………………………[3] (b) Suggest a limitation to the setup in measuring the rate of transpiration. ………………………………………………………………………………………………[1] (c) Suggest the significance of the plastic bag in the setup. ………………………………………………………………………………………………[1] [Total: 5] plant plastic bag pot of soil electronic balance

9 Tanjong Katong Girls’ School Sec 4 Preliminary Examination 2024 6 Fig. 6.1 shows how a molecule o