KCPSS 2024 4E SciBio Prelim P4

1 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over KUO CHUAN PRESBYTERIAN SECONDARY SCHOOL 2024 PRELIMINARY EXAMINATION Secondary 4 Express / 4 Normal Academic (SBB) NAME CLASS REG. NO SCIENCE (CHEMISTRY/BIOLOGY) 5088 / 04 Paper 4 Biology Paper 4: 1 hour 15 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your class, index number and name on all the work you hand in. Write in dark blue or black pen on both sides of the paper. You may use an HB pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. 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. Section A Answer all questions. Write your answers in the spaces provided on the question paper. Section B Answer one question. Write your answers in the spaces provided on the question paper. The number of marks is given in brackets [ ] at the end of each question or part question. FOR EXAMINER’S USE Section A Section B Total This document consists of 21 printed pages, including the cover page. ………….……...…….....…... Parent’s signature/ Date

2 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over Section A Answer all questions. Write your answer in the spaces provided. 1 Fig. 1.1 represents an enzyme and substrate involved in a reaction which takes place in the mouth. Fig. 1.1 (a) Name A and B. A ………………………………………………………….….…………………….. B ………………………………………………………….….…………………….. [1] (b) In the space below, draw the enzyme-substrate complex and the final products formed during the reaction. Label your drawing. enzyme-substrate complex final product [2] substrate A enzyme B

3 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over (c) A student carried out the Benedicts’ test on a solution of substrate A and a solution consisting of the final products drawn in (b). Predict the observation for the two solutions. solution of the substrate A ………………………………………………………….…. solution of final products in (b) ………………………………………………….….… [1] [Total: 4] 2 Fig. 2.1 represents what the human alimentary canal would look like if it was removed from a person and straightened out. Fig. 2.1 (a) (i) Identify parts A to D. A ……………………………… B ……………………………… C ……………………………… D ……………………………… [2] (ii) Diarrhoea is a condition where a patient has watery stools. State which part, A – D, is likely to be affected in this condition. ………………………………………………………………………………... [1] A B D C not drawn to scale

4 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over (b) Fig 2.2 shows a person’s blood glucose concentration before and after a meal containing carbohydrates is eaten. Fig. 2.2 (i) State one function of insulin. ………………………………………………………….….……………………….. ………………………………………………………….….…………………. [1] (ii) A person suffering from type 1 diabetes is unable to make insulin. This person normally receives an injection of insulin before a meal. With reference to Fig. 2.2, p redict the shape of the graph if this person did not receive an insulin injection. ………………………………………………………….….……………………….. ………………………………………………………….….…………………. [1] [Total: 5] meal eaten blood glucose concentration time

5 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over 3 Fig. 3.1 shows an angiogram of a heart before treatment for coronary heart disease. An angiogram is an image of the blood flow through the blood vessels on the surface of the heart. Fig. 3.1 The arrow on Fig. 3.1 shows the position of a blockage in a blood vessel due to a blood clot. (a) State the name of the blocked blood vessel. ………………………………………………………….….……………………….. [1] (b) State one factor, other than diet, that can increase a person’s risk of developing coronary heart disease. ……………………………………………………………………………………… [1] blockage

6 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over (c) Suggest and explain how this blockage in Fig. 3.1 may affect the heart. …………………………………………………………………………………….……… …………………………………………………………………………………….……… …………………………………………………………………………………….……… …………………………………………………………………………………….……… …………………………………………………………………………………….……… …………………………………………………………………………………….……… …………………………………………………………………………………….……… ……………………………………………………………………………………… [4] [Total: 6]

7 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over 4 (a) Fig. 4.1 shows a setup with a number of respiring maggots placed in a large test tube. The apparatus was left for 20 minutes and then a drop of coloured liquid was introduced into the capillary tube as shown. Fig. 4.1 (i) What is the function of sodium hydroxide in the setup? ………………………………………………………………………………... [1] (ii) Explain why the drop of coloured liquid moved towards the boiling tube. ……………………………………………………………………………………… ………………………………………………………………………………... [1] rubber tubing scale glass tubing maggots wire gauze sodium hydroxide capillary tube coloured liquid clip

8 KCPSS 2024/Sec 4Exp/SBB Prelim Sci (Bio) P4 [Turn Over (b) Humans respires similarly to maggots, but a by-product called lactic acid may be present in the human muscle cells. Table 4.1 shows the concentration of lactic acid and glycogen in a person’s leg muscle. The measurements were made at rest and after vigorous exercise. Table 4.1 concentration in leg muscle / arbitrary units at rest after vigorous exercise lactic acid 0.9 23.5 glycogen 75.0 22.0 (i) Explain the decrease in glycogen concentration in the muscle after a vigorous exercise. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ………………………………………………………………………………... [2] (ii) Explain the increase in lactic acid concentration in the muscle after a vigorous exercise. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ………………………………………………………………………………... [2] [Total: 6]

9 KCPSS 2024/Sec 4Exp/SBB Prelim Sci