Secondary 2 Geography Physical Geography Quiz

Secondary 2 Geography Quiz - Physical Geography (Answer Key)

Total Marks: 40
Topic: Physical Geography (Stage 5 AI-generated, syllabus-first; not claimed as past-year derived)

Q1. [1 mark] C. Biosphere
Teaching note: The biosphere is the sphere that contains all living things (plants, animals, microbes). Atmosphere = air; lithosphere = solid earth/rocks; hydrosphere = water. Common mistake: confusing biosphere with hydrosphere.

Q2. [1 mark] Condensation
Teaching note: Cooling of water vapour → liquid droplets = condensation, forming clouds. Evaporation is the reverse (liquid → vapour).

Q3. [1 mark] Solid
Teaching note: Glaciers are frozen water, so the state is solid. Other states: liquid (oceans), gas (water vapour).

Q4. [2 marks] Any two of: oceans, glaciers, rivers, lakes, groundwater, atmosphere (water vapour). [1 mark each]
Teaching note: These are stores in the hydrological cycle. Mark both correctly named stores.

Q5. [1 mark] Water budget
Teaching note: Water budget = balance of inputs (rain) and outputs (evaporation, runoff) in a catchment.

Q6. [1 mark] Emergent layer
Teaching note: From the placeholder diagram, the tallest layer with trees above canopy is the emergent layer (30–45 m). Common mistake: writing "canopy".

Q7. [1 mark] Aerial roots / prop roots / pneumatophores
Teaching note: These roots stick above mud to take in air (oxygen) since soil is waterlogged.

Q8. [2 marks] Any two of: habitat for biodiversity, carbon storage, oxygen production, erosion protection, climate regulation. [1 mark each]
Teaching note: Rainforests provide many environmental functions; accept clear ecological roles.

Q9. [3 marks] Mark scheme:

• States overall trend: water surplus decreases from Jan to July (1 mark)
• Uses statistics: Jan surplus = 120–60 = 60 mm; July rainfall 35 < evapotranspiration 130 → deficit of 95 mm (1 mark)
• Notes crossing point: by May/Jun rainfall < evapotranspiration (1 mark)
  Teaching note: Water surplus = rainfall − evapotranspiration. In Jan it is +60 mm, shrinking to negative by Jul. Student must refer to numbers.

Q10. [2 marks] (a) June (b) July [1 mark each]
Teaching note: Jun: 40 < 125; Jul: 35 < 130. Also May and Aug close but May rain 50<110, Aug 38<128 — accept May, Jun, Jul, Aug if consistent; best two clearly deficit: Jun, Jul.

Q11. [3 marks]

• Description: visible aerial/prop roots above water (1 mark)
• Explanation: allows gas exchange in oxygen-poor muddy soil (1 mark)
• Context: helps survival in waterlogged coastal conditions (1 mark)
  Teaching note: From photo, roots are adaptation for breathing; link to environment.

Q12. [3 marks]
Working: Total = 100%. Usable lakes/rivers = 0.1%. Not usable = 100 − 0.1 = 99.9% (2 marks for working + answer).
Teaching note: Most water is salty ocean or locked in ice; only 0.1% is accessible freshwater surface water.

Q13. [2 marks]

• Near Equator temperatures are high all year (1 mark)
• High temperatures cause high evaporation → frequent convectional rainfall (1 mark)
  Teaching note: Tropics have warm, wet climate suitable for rainforests.

Q14. [3 marks]
Calculation: Decrease = (5000 − 3200) / 5000 × 100 = 1800/5000 × 100 = 36% (2 marks).
Explanation: Less forest means less carbon stored, more CO₂ in air (1 mark).
Teaching note: Formula: % decrease = (loss/original)×100. Deforestation releases stored carbon.

Q15. [4 marks] Mark descriptors:

• Defines evaporation: sun heats water → vapour rises (1)
• Links to cloud/rain formation over Singapore (1)
• Connects to local catchment tap: rain fills reservoirs (1)
• Notes without evaporation, no rainfall, supply fails (1)
  Teaching note: Evaporation from sea is key to Singapore's local catchment water.

Q16. [4 marks]

• Characteristic: dense continuous roof of trees 20–30 m, blocks light (2)
• Supports biodiversity: many species live/feed there, microhabitats (2)
  Teaching note: Canopy is most biologically active layer.

Q17. [4 marks]

• Explains salt secretion removes excess salt from salty water (2)
• Evaluates: effective for survival but limited if salinity extreme / cannot survive long flooding (2)
  Teaching note: Adaptation has threshold; not perfect.

Q18. [4 marks] Chain: trees cut → less CO₂ absorbed (1); stored carbon released by burning/decay (1); more atmospheric CO₂ (1); stronger greenhouse effect (1).
Teaching note: Systems thinking: forest loss = carbon source.

Q19. [3 marks]

• Water cycles but distribution uneven (1)
• Humans need accessible freshwater, not salt/ocean (1)
• Local shortages occur despite cycle (1)
  Teaching note: Renewable ≠ always available where needed.

Q20. [4 marks]

• Roots/trunks absorb wave energy → less erosion (2)
• Limitation: if storms too big or mangroves narrow, protection fails (2)
  Teaching note: From diagram, belt buffers village; evaluate limit.