Sharing Session on Science Answering Techniques Objectives of Sharing Session Introduce four basic skills involved in answering Science questions Provide hands-on practice in applying the skills in analysing Science questions Pei Chun Public School

Science Exam Skills Skill A – Correct interpretation of diagram Skill B – Identify the aim of experiment Skill C – Identify the underlying Science concept Skill D – Draw an informed inference Pei Chun Public School

Skill A – Correct Interpretation of Diagram First step in identifying the underlying Science concept Crucial to the correct understanding of the question Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) Matthew performed an experiment using two set-ups, X and Y, as shown below. He placed three beans into each set-up and left them in a room with a temperature of 30 C. cooled boiled water tap water X Y oil Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) After two days, he noticed that the beans in Beaker Y germinated but those in Beaker X did not. Explain his observation. cooled boiled water tap water X Y oil Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) Hint: Why is there a need for boiled water? Boiled water lacks dissolved oxygen/air. Tap water contains dissolved oxygen/air. Hint: Why is there a need for the layer of oil? The layer of oil prevents atmospheric oxygen from dissolving in the water. Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) Answer: is needed for germination. There is dissolved in water for the beans in Beaker to germinate but not for the beans in Beaker . Oxygen oxygen tap Y X Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) Answer: General Fact: is needed for germination. Specific Application: There is dissolved in water for the beans in Beaker to germinate but not for the beans in Beaker . Oxygen oxygen tap Y X Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) cooled boiled water tap water X Y oil Higher-order Thinking Why use three beans? Increases the success rate of the experiment Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Example) Higher-order Thinking Why is there a need for the layer of oil in Beaker Y as shown above? The layer of oil prevents the evaporation of water. oil tap water tap water X Y Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A1) Eunice carried out an experiment by heating a test-tube containing crushed ice, steel wool and water as shown below. What did Eunice's experiment show? steel wool water ice Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A1) Hint: What is the purpose of the steel wool? The steel wool prevents the crushed ice from floating to the water surface, thus preventing the ice from being under the direct heat source. steel wool water ice Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A1) Answer: The experiment showed that is a . water poor/bad conductor of heat OR insulator of heat Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A1) Answer: The experiment showed that is a . Note:  non-conductor Reason: All matter - conductors of heat. water poor/bad conductor of heat OR insulator of heat Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A2) Andrew spread a layer of oil on the plant as shown below. The plant was then placed in the sun and watered every day. After a week, the plant wilted. Explain why the plant wilted. oil applied on the stem, leaf stalks and both surfaces of all the leaves Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A2) Hint: What is the result of coating the plant with a layer of oil? The stomata are blocked. The exchange of gases through the leaves cannot be carried out. Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A2) Answer: could not take place as the exchange of gases through the leaves could not be carried out. could not take place as the plant parts covered with oil could not take in oxygen. could not take place as the plant could not give out water vapour to keep itself cool. ( not in syllabus) Photosynthesis Respiration Transpiration Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A2) Explain why the plant wilted. Pupils must identify one of the underlying plant processes that have been affected. Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A2) Explain why the plant wilted. Pupils must identify one of the underlying plant processes that have been affected. Partial/incomplete answer: The stomata are blocked. The exchange of gases cannot be carried out. Pei Chun Public School

Skill A – Correct Interpretation of Diagram (Question A2) What is the result of coating the plant with a layer of oil? The stomata are blocked. The exchange of gases cannot be carried out. The above answer is acceptable in this case as the question is asking for the immediate effect. Pei Chun Public School