Public Assessment of the HKDSE Biology Examination

Transcription

1 Public Assessment of the HKDSE Biology Examination 1. Public Assessment The public assessment of the Hong Kong Diploma of Secondary Education (HKDSE) Biology Exam consists of a public examination component and a school-based assessment component. A. Public Examination component In Biology, the mark of the public examination component contributes 80% of the final subject mark. Paper Section Question types Weighing Duration Curriculum Section A Multiple-choice Questions 18% 2 hours Paper 1 Short Questions and Structured Compulsory Part Section B 42% 30 minutes / Essay-type Questions Elective Part Paper 2 Structured Questions 20% 1 hour (2 out of 4) B. School-based Assessment component In Biology, students are assessed by their teachers on their performance of a wide range of skills involved in practical related task throughout S.5 and S.6. The mark of the school-based assessment component contributes 20% of the final subject mark. Year of examination Assessment types Weighing Starting from 2012 Practical related component 20% 2. Standards-referenced Reporting The HKDSE makes use of standards-referenced reporting, which means candidates levels of performance will be reported with reference to a set of standards as defined by cut scores on the variable or scale for a given subject. The following diagram represents the set of standards for a given subject: Cut scores U Variable/ scale Within the context of the HKDSE there will be five cut scores, which will be used to distinguish five levels of performance (1 5), with 5 being the highest. The Level 5 candidates with the best performance will have their results annotated with the symbols and the next top group with the symbol. A performance below the threshold cut score for Level 1 will be labelled as Unclassified (U). II

2 Exam Strategies A. Time Allocation Paper 1 (Compulsory Part) 2 hours 30 minutes Section Suggested Time Allocation Approximate Time per Question A 45 minutes minutes B 105 minutes 5 10 minutes Allow 5 minutes for final checking. Paper 2 (Elective Part) 1 hour Time Allowed Approximate Time per Question 60 minutes (answering 2 out of 4 questions) minutes Allow 5 minutes for final checking. B. Answering Skills Paper 1A Multiple-choice Questions Mark only ONE answer for each question. DO NOT leave any questions unanswered even if you do not know the answer. Eliminate the incorrect options to choose the answer or even use wild guessing, if and only if you have no idea about the answer. DO NOT spend too much time in reading the options but pay attention to any key terms when you first read it. One or two incorrect terms make the whole concept incorrect. Pay attention to words like all, always, every, never,and none. Because there are no exceptions to the statement when these words are used the statement has higher chance to be incorrect. Circle questions that you are not sure about the answers so that you can identify and review the questions quickly in the final checking. Paper 1B and Paper 2 Short Questions and Structured / Essay-type Questions Skip the questions that you do not have confidence on. Go back to those questions after you have finished the others. Remember to write down both steps and answers for questions involving calculation. You can obtain marks for the steps even your answer is incorrect. Remember to write down a unit for your answer. Sometimes, you can copy the unit from the question. III

3 2012 HKDSE Exam and Mock Exam Questions Distribution Paper 1 (Compulsory Part) Paper 1A consists of 36 MC questions and Paper 1B consists of 84 marks. Distribution of Exam Questions: Topics 2012 HKDSE Mock 1 Section A Section B Section A Section B I. Molecules of life 3 II. Cellular organization 1 III. Movement of substances across membrane 23, 24, 25 1 IV. Cell cycle and division 11 16, 34 V. Cellular energetics 2, , 19 4, 12 VI. Basic genetics , 26, 27 8 VII. Molecular genetics 18, 19 VIII. Biodiversity and evolution 4 11 IX. Essential life processes in plants 3, 10, 11, 12 3, 5 22, 31, 32 7 X. Essential life processes in animals 20, 21, 22, 31, 32, 33, 34, 36 1, 10 7, 11, 15, 33 3 XI. Reproduction, growth and development 13, 14, 24, 25, 26, 27, 28, 29 XII. Coordination and response 4, 5, 6, 7, 8, 9, 30 14, 17, 18, , 5, 6, 13, 20, 29, 30 XIII. Homeostasis XIV. Ecosystems 16, , 4, 10, 21, 35, XV. Personal health XVI. Diseases 2 2 XVII. Body defence mechanisms 35 About 70% of the questions are set at the former HKCE Examination level. The rest (30% of the questions) are set at the former HKAL Examination level. 5 Paper 2 (Elective Part) Paper 2 consists of four questions (20 marks each). Candidates should answer two questions. VI

4 Common Mistake Analysis 1. Title and labels are not given when drawing a labelled diagram. E.g.: Draw a labelled diagram of a plant cell. Wrong answer: Correct answer: Drawing of a plant cell cell wall cell membrane cytoplasm nucleus (Note: Draw simple 2-D line diagrams. Unless specified in the question, there is usually no need to draw 3-D diagrams. The labelling line for a label should touch the named part.) 2. For questions involving calculations, the unit of the answer is not given. E.g.: 5 cm 3 of water is loss by a plant in 30 minutes. Calculate the rate of water loss of the plant. Wrong answer: Correct answer: 5 30 = = cm3 /minute 3. No key or labels are given to a graph with two independent variables. E.g.: Plot a graph to show the yield of wheat when different amounts of inorganic fertilizers are added in the presence and in the absence of fungicides. Wrong answer: Correct answer: With the addition of fungicides Yield of wheat (arbitrary unit) Yield of wheat (arbitrary unit) Without the addition of fungicides Mass of inorganic fertilizers added (kg) Mass of inorganic fertilizers added (kg) VIII

5 Directions: Questions 14 and 15 refer to the photograph below which shows a section of a pig s heart. R S T U V 14. Which of the following descriptions about the structures is correct? A. Structure R contracts to force blood down into the left ventricle. B. Structure S prevents the backflow of blood into the aorta when the left ventricle contracts. C. Structure T contracts to force blood into the lungs through the pulmonary vein. D. Structure U prevents structure S from turning inside out when the right ventricle contracts. 15. Which of the following combinations about structure S and its function is correct? Structure S Function A. bicuspid valve separate oxygenated blood from deoxygenated blood between the left and right ventricles B. bicuspid valve prevent the backflow of oxygenated blood into structure R C. tricuspid valve separate oxygenated blood from deoxygenated blood between the left and right ventricles D. tricuspid valve prevent the backflow of oxygenated blood into structure R MOCK 2 PAPER 1A Hong Kong Educational Publishing Co.

6 9. Parkour is an activity involving skillful body movement. It consists of small jumps, runs, climbing or other aerobic activity to move from one point to another using the physical setting of the surrounding environment. This activity provides intensive training to the strength, balance, response and conditioning of the players. The handstand is one of the skills of Parkour. joint X Answers written in the margins will not be marked. (a) Name the type of joint that joint X belongs to. State one characteristic of its movement. (2 marks) Answers written in the margins will not be marked. (b) This player decided to further bend his left leg to increase the level of difficulty of the posture. Use a flowchart to show the nervous pathway for bringing about the action by including major neurone(s), part(s) of the central nervous system and the effector involved. (2 marks) Answers written in the margins will not be marked. MOCK 4 PAPER 1B Hong Kong Educational Publishing Co. Page total

7 Section B Applied Ecology Answer ALL parts of the question. 2. (a) The diagram below shows a sewage treatment plant. The arrows show the direction of sewage movement. raw sewage grid grid chamber sedimentation tank liquid part (effluent) gas solid part (sludge) sprinkler sludge digester liquid spray safe effluent percolating filter (i) What type of waste is processed by the sewage treatment plant? (1 mark) (ii) What is the function of the grid? (1 mark) (iii) What condition must be provided to the sludge digester for breaking down the sludge? Explain why it is necessary. (2 marks) (iv) Describe and explain two observable features of the percolating filter that are essential for the completed break down of wastes in the sewage. (4 marks) (v) Explain why the stones on the top layer of the percolating filter are green in colour while those at the bottom are not. (3 marks) MOCK 4 PAPER Hong Kong Educational Publishing Co.

8 Mock Exam Occurrence: Calvin cycle takes place in plant cells while the Krebs cycle takes place in both plant and animal cells. 0 CO 2 is captured in the Calvin cycle while CO 2 is removed from the reactant in the Krebs cycle. 0 Nature of the biochemical reactions: The Calvin cycle is an anabolism while the Krebs cycle is a catabolism. 1 CO 2 is used up in the Calvin cycle while glucose is removed in the Krebs cycle. 0 NADPH is found in the Calvin cycle while NADH and FADH are found in the Krebs cycle. 1 ATP is used up in the Calvin cycle while ATP is produced in Krebs cycle. 1 The Calvin cycle is a reduction process while the Krebs cycle is an oxidation process. 1 The candidate s response shows a basic knowledge and understanding about the occurrence and nature of the Calvin cycle and Krebs cycle. However, the candidate fails to state the exact location and fails to give detailed descriptions of reactants and types of electron carriers involved in both cycles. State the exact location and give detailed descriptions for both cycles. 12. Occurrence: Calvin cycle takes place on the thylakoid membranes of chloroplasts in plant cells which undergo photosynthesis while the Krebs cycle takes place in the matrix of mitochondria in all living cells which undergo respiration. 1 CO 2 is captured by a 5-C compound in the the Calvin cycle while CO 2 is removed from the reactant in the the Krebs cycle. 1 Nature of the biochemical reactions: Calvin cycle is an anabolism while the Krebs cycle is a catabolism. 1 Inorganic CO 2 is used to form organic triose phosphate in the Calvin cycle while organic glucose is broken down into inorganic CO 2 in the Krebs cycle. 1 The type of electron carriers involved in the Calvin cycle is NADPH which is used up, while those in the Krebs cycle are NADH and FADH which are produced. 1 ATP is used up in the Calvin cycle while ATP is produced in Krebs cycle. 1 The candidate s response shows an extensive knowledge and thorough understanding about the occurrence and nature of Calvin cycle and Krebs cycle. He / she can state the exact location, and gives detailed descriptions of the reactants and types of electron carriers involved in both cycles. The Calvin cycle is a reduction process while the Krebs cycle is an oxidation process. 1 Communication max Hong Kong Educational Publishing Co.

9 Mock Exam 1 (b) (i) Afferent arteriole 1 (ii) The blood in vessel P has more oxygen 1 and less carbon dioxide. 1 (iii) The high blood pressure in the glomerulus 1 forces some plasma, except for large proteins and blood cells, out of the glomerulus 1 through the walls of the glomerulus, and into the space of Bowman s capsule. 1 Thus, the fluid entering the capsule forms the glomerular filtrate. (iv) A longer loop of Henle increases water reabsorption. 1 More concentrated urine can be produced to conserve water for the mammals to survive. 1 (v) Glucose 1 Amino acid 1 The detailed mechanism on how the loop of Henle increases water reabsorption is out of the HKDSE syllabus. However, candidates should have basic concept about the function of the loop of Henle. Section B Applied Ecology 1. (a) (i) SENT is next to the country park. 1 The expansion of SENT destroys the nearby habitats for local flora and fauna species. 1 This reduces the biodiversity of the nearby area. 1 (ii) (1) NENT WENT New Territories Kowloon Hong Kong Island SENT A cross mark on a rural area 1 The site should be away from country parks, residential and commercial areas. 1 Landfill is different from reclamation. The landfill (2) Incineration 1 site cannot be used to (3) For recreational purposes 1 construct new buildings and (iii) (1) there are many toxic gases released from it. They can only be used for recreational = 44.4% 45.1% purposes. = 0.7% 1 (2) Clinical waste 1 Sludge from sewage treatment 1 (b) (i) The total area of closed tropical rainforest in Papua New Guinea remains unchanged. 1 The decrease in the total area of closed tropical rainforest in Brunei was more than the decrease in Malaysia. 1 Candidates should first divide the data into groups, and then describe each group one by one Hong Kong Educational Publishing Co.