PLMGS EOY 2025 Geog 1G3 Ans

Subject : Geography (G3) Date 29 September 2025 Duration : 1 hour 30 minutes Name : _________________________ ( ) Class : ______ (TG ______ ) Teacher :__________________ Instructions to Candidate: Do not open this booklet until you are told to do so. Write your answers in the space provided in the question booklet. Write in dark blue or black pen. Do not use paper staples, paper clips, glue or correction fluid. You must answer all questions. The number of marks is given in brackets [ ] at the end of each question or part question. The total marks for this paper is 50. ______________________________________________________________________ This document consists of 12 printed pages. FOR TEACHER’S USE Question 1 • Water /30 Question 2 • Tropical Forests /20 Total /50 Paya Lebar Methodist Girls’ School (Secondary) End-of-Year Examination 2025 Secondary 1 Marking Scheme [Turn over

2 Section A: Water – 30 Marks 1 (a) Study Fig. 1.1 which shows a diagram of the hydrological cycle. Fig. 1.1 (i) With reference to Fig. 1 .1, identify processes X, Y and Z in the hydrological cycle. Process X: Percolation [1] Process Y: Evaporation [1] Process Z: Precipitation [1] Answers with slight spelling errors will still be marked as correct. However, answers like ‘proculation, perlocation, procalation’, ‘evaporistation’ were not accepted. (ii) Explain how the processes of the hydrological cycle renew Earth’s water supply. [4] • The heat from the sun warms the water in the oceans. Water evaporates and rises into the air. • Water vapour condenses into water droplets which gather to form clouds. • When water droplets that form the clouds become too heavy, they fall as precipitation. • Some precipitation infiltrate into the ground/percolates through the soil layers.

3 • Precipitation runs off the land/ flows away as surface runoff and into the rivers. 4 points @ 1 mark each Answers must include the words in bold, highlighting the key processes in the hydrological cycle and how they contribute to a renewable water supply. (b) Study Fig. 1.2 which shows the percentage of water used for different purposes in six areas of the world. Fig. 1.2 (i) Using Fig. 1.2, identify the area with the highest percentage of water in agricultural use. [1] Central Asia [1] (ii) Using Fig. 1.2, describe the difference in percentage of water in industrial use between North America and Africa. [1] • North America uses a higher percentage of water in industrial use, at 48% compared to Africa which has a lower percentage of water in industrial use at 7%. [1]

4 Answers which indicated that North America uses 41% more water for industrial use are also accepted. Zero mark will be given if student does not quote the date from Fig. 1.2. Data quoted must also be accurate. (iii) Suggest an activity in which water is used domestically. [1] Showers, Cooking etc [1] Accept any plausible answer Answers like ‘drinking water’, ‘cleaning’ and washing hands with water are not accepted as they are not activities which are mainly carried out at home (domestic). (c) Study Fig. 1.3 which shows percentage of population with access to safe drinking water. Fig. 1.3 (i) Using Fig. 1.3, identify two countries where 91% or more of the population have access to clean drinking water. [2] Canda, USA, China, India etc Any 2 possible countries at 1 mark each, Max 2 marks

5 Answers which quoted continents (e.g. North/South America, Asia) are not accepted as question clearly requires students to identify countries. (ii) Using Fig. 1.3 describe the distribution of countries where 75% or less of the population have access to clean drinking water. [3] • Most of these countries are in the continent Africa, with the exception countries like South Africa and Egypt • Quite a number of these countries can be found in South East Asia. • A few countries like Mongolia and Indonesia can be found in Asia. • Many of these countries are near the equator/between the tropic of cancer and tropic of Capricorn 3 points @ 1 mark each Many students did not do so well for this question as they have not grasped the meaning of distribution – which requires students to identify spatial patterns. Places with high and low concentration of countries where 75% or less of the population have access to clean drinking water. (d) Explain how flash floods can occur in highly built-up urban areas. [3] • When there is exceptionally heavy rainfall over a short period of time • In built up urban areas, most of the road surfaces are made of concrete, cement or other non porous materials, which does not allow rainwater to infiltrate the ground • Most of the rainwater that falls onto the ground becomes surface runoff which quickly floods low-lying areas. 3 points @ 1 mark each Answers must include words in bold, which highlight the distinctive features of a flash flood and how it is formed in a built -up urban area. Students are also reminded to use geographical terms such as infiltrate instead of layman terms like ‘get absorbed’ or ‘seep into’ (e) Fig. 1.4 and 1.5 show human activities which can cause water pollution.

6 Fig. 1.4 Fig. 1.5 (i) Describe the human activities shown in Fig. 1.4 and 1.5 which can contribute to water pollution. [2] • Excess fertilisers and pesticides from farms may get washed into rivers by rain providing additional nutrients for algae to grow rapidly. • Some factories may release untreated or poorly treated toxic chemicals directly into rivers, lakes, or oceans. 2 points @ 1 mark each Since there are many types of chemical waste, for Fig. 1.5, students must be able to identify that the waste come from factories/production plants or state that it is industrial waste. Answers like ‘toxic chemicals’, ‘waste’, ‘chemials’ were no accepted.

7 (ii) Explain how humans and the physical environment would be affected by such water pollution. [5] • Excess fertilisers in the water bodies may cause algae bloom. • When the algae eventually die, they are decomposed by bacteria, which take in oxygen during the process. • As a result, less oxygen remains in the water, causing fish and other aquatic animals to die. • Toxic chemicals in the water may contaminate surface and ground water, cause aquatic plants and animals to die in polluted waters. • Some toxins build up in the bodies of animals over time, moving up the food chain and affecting birds, humans, and other predators • Humans may suffer from water borne diseases from consuming contaminated groundwater. • Humans may have insufficient clean drinking water source due to polluted groundwater source. Any 5 points @ 1 mark each Weaker answers tend not to mention about how the use of fertilisers and pesticides can lead to algae bloom and other associated effects. Answers might also not show the chain effect of water pollution on the wider biodiversity.

8 (f) Study Fig. 1.6, which is an article on how technology has been used to produce freshwater. Fig. 1.6 (i) With reference to Fig. 1.6, state the strategy used in Singapore to ensure long-term water sustainability. [1] NEWater [1] Also accepted: Improving Water Quality, Improving Water Technologies, Treating/recycling waste water to clean water Not accepted: Recycling, Renewing water, Reusing water, reverse osmosis (ii) Describe one advantage and one disadvantage of using this strategy in Singapore [2] Advantages: • NEWater is weather-independent, unlike rain-fed reservoirs, making it a reliable supply during dr