Cambridge O-Level Environmental Management: Water — Practice Questions (5014, 2027-2029)

These questions cover all six sub-topics of Topic 3 Water in the 2027-2029 Cambridge O Level Environmental Management (5014) syllabus. They test recall, source interpretation and the “discuss the benefits and limitations” skill that appears throughout the papers.

These are original questions written for Marlbridge, for revision and practice on this content. They are not reproduced past-paper questions, and they do not replicate the exam’s exact structure, question count or mark tariffs — examination boards hold copyright in their own papers. Use these alongside the official past papers available free from your board.

Related: Water study guide (2027-2029) | Water revision notes

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Section A

1. Name the five oceans of the world. [2]

2. Define potable water. [1]

3. State the length that defines a microplastic. [1]

4. Name the parasite that causes malaria. [1]

Section B

5. (a) Name two stores of fresh water and two transfers in the water cycle. [2] (b) Explain how removing forest from a river basin changes interception and surface run-off. [2]

6. Describe the four stages used to make river water potable, in order. [4]

7. Explain why access to potable water is often lower in rural areas of low-income countries than in cities. [2]

8. A small island has no rivers and a growing tourist industry. It plans a reverse osmosis plant. (a) Describe how reverse osmosis produces fresh water. [2] (b) Discuss one benefit and one limitation of desalination for the island. [2]

9. A factory discharges mercury into an estuary. Fishermen and seabirds both eat fish from the estuary. (a) Explain why the seabirds have higher concentrations of mercury than the fish. [3] (b) Suggest two strategies to improve the water quality of the estuary. [2]

10. Describe how malaria is transmitted between humans and mosquitoes. [3]

11. A village has had a cholera outbreak after floods. Describe three strategies to control cholera in the village. [3]

12. (a) Define marine aquaculture. [1] (b) Explain two negative impacts of a fish farm in a sheltered bay on the surrounding marine ecosystem. [4]

13. Explain how increasing the mesh size of nets and closed seasons help manage fish stocks. [4]

14. (a) State three causes of oil pollution in coastal waters. [3] (b) Describe how oil affects seabirds and coral reefs. [3]

15. Distinguish between bioplastics and biodegradable plastics. [2]

Section C

16. Discuss the benefits and limitations of booms, detergent sprays and controlled burning for minimising the impacts of an oil spill. [6]

17. Discuss the benefits and limitations of strategies to control malaria. [6]

18. Discuss whether recycling is a more effective strategy than legislation for reducing plastic pollution in the oceans. [6]

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Answers

1. Pacific, Atlantic, Indian, Southern, Arctic. [2] (All five for 2 marks; three or four for 1.)

2. Water that is safe to drink. [1]

3. Less than 5 mm. [1]

4. Plasmodium. [1]

5. (a) Stores, any two: ice sheets and glaciers, ground water, atmosphere, lakes and rivers [1]. Transfers, any two: precipitation, interception, surface run-off, infiltration, through-flow, ground water flow, transpiration, evaporation, condensation [1]. (b) Fewer trees intercept rainfall [1], so more water reaches the ground quickly and surface run-off increases [1].

6. Screening removes large objects [1]; sedimentation lets particles settle [1]; filtration removes fine particles [1]; chlorination kills bacteria [1].

7. Rural areas are often far from piped supplies and treatment plants [1], and governments may lack money to extend infrastructure to scattered populations [1].

8. (a) Sea water is put under high pressure and passed through a membrane [1], which lets water molecules through but stops most ions [1]. (b) Benefit: a reliable supply independent of rainfall for residents and tourists [1]. Limitation: high energy use and cost, and brine waste can harm marine life [1].

9. (a) Mercury builds up in each fish over time (bioaccumulation) [1]; seabirds eat many fish [1], so mercury becomes more concentrated at each level of the food chain (biomagnification) [1]. (b) Any two: pollution control and legislation on discharges [1]; treatment of industrial waste before release [1]; monitoring and fines [1]. [max 2]

10. A female Anopheles mosquito carrying Plasmodium bites a human, passing the parasite into the blood [1]; an uninfected mosquito becomes infected when it feeds on the blood of an infected person [1]; it can then infect another person [1].

11. Any three: handwashing with soap [1]; boiling or chlorinating drinking water [1]; repairing sanitation and sewage treatment [1]; vaccination [1]. [max 3]

12. (a) The farming of marine species (fish, crustaceans or seaweeds) in captivity. [1] (b) Any two explained: waste and uneaten feed cause nutrient enrichment [2]; disease spreads to wild fish [2]; escaped farmed fish compete or interbreed with wild fish [2]; feed made from wild-caught fish puts pressure on other stocks [2]. [max 4]

13. Larger mesh lets young, small fish escape [1], so they survive to breed and replace the stock [1]. Closed seasons stop fishing at certain times, such as the breeding season [1], allowing populations to recover [1].

14. (a) Any three: offshore or onshore oil extraction; pipelines; shipping accidents; cleaning tanks at sea; refineries. [3] (b) Seabirds: oil coats feathers, so they lose insulation and buoyancy and may swallow oil when preening [2]. Coral reefs: oil smothers coral and blocks light [1].

15. Bioplastics are made fully or partly from biological raw materials and may or may not be biodegradable [1]; biodegradable plastics are designed to be decomposed by bacteria and fungi in water or soil, whatever they are made from [1].

16. [6] Booms: contain oil so it can be skimmed or absorbed with sorbents; limited in rough seas. Detergent sprays: break oil into droplets that disperse; but detergents can be toxic to marine life and the oil remains in the water. Controlled burning: removes large amounts quickly at sea; but causes air pollution and works only on fresh, thick oil in calm conditions. Conclusion: a combination is used, chosen for sea conditions and nearness to coasts.

17. [6] Personal protection: nets and repellent are cheap and effective at night; vaccination and antimalarial drugs reduce severe illness; but nets must be used correctly, drugs cost money and parasites can become resistant. Vector control: draining breeding sites removes larvae; spraying kills adults; sterile male release and biological control reduce numbers without chemicals; but insecticides harm other species and mosquitoes can become resistant, and draining wetlands harms habitats. Conclusion: combined strategies work best.

18. [6] Recycling: reuses plastic and reduces new production, but many plastics are not recycled, it needs collection systems, and plastic already in the ocean is not removed. Legislation and enforcement: bans on single-use items or microbeads reduce plastic at source and apply to everyone, but enforcement is difficult and plastic crosses borders. Conclusion: legislation that reduces use is likely to be more effective, supported by recycling and safe disposal.

Where marks are usually lost

• Writing “chemicals” instead of naming chlorination at the end of water treatment.
• Describing biomagnification without referring to feeding levels.
• In “discuss” items, describing how a method works but giving no limitation.

Frequently asked questions

Which oil spill strategies are prevention and which minimise impacts? Prevention: MARPOL, double-hulled tankers, risk assessments and maintenance. Minimising impacts: navigation systems, booms and sorbents, detergent sprays, skimmers and controlled burning.

Do I need specific fish species for aquaculture? No. The syllabus says knowledge of specific species is not required; refer to fish, crustaceans and seaweeds.

How are malaria and cholera controls different? Malaria is controlled by avoiding bites and reducing mosquitoes. Cholera is controlled by clean water, sanitation, hygiene and vaccination.

Official syllabus

Cambridge O Level Environmental Management (5014) syllabus for 2027, 2028 and 2029 - official syllabus PDF.