Sub. Code 4141
NEB - GRADE XII
Model Question
2079(2023)
Environmental Science
Candidates are required to give their answers in their own words as far as practicable.
Attempt all the questions
Group 'A'
1. What does hydrological cycle mean?
Answer: The hydrological cycle, or water cycle, is the continuous circulation of water within the Earth-Atmosphere system, driven by solar energy. It involves key processes like evaporation, condensation, precipitation, and runoff.
2. Define lithosphere in one sentence.
Answer: The lithosphere is the rigid, outermost rocky shell of a planet, consisting of the crust and the upper portion of the mantle.
3. Give a reason for using quantification techniques in biodiversity assessment.
Answer: Quantification techniques are used in biodiversity assessment to measure and monitor the decline or changes in species, helping to inform and guide conservation efforts.
4. Clarify the meaning of climate change.
Answer: Climate change refers to long-term shifts in temperatures and weather patterns, primarily caused by human activities such as the burning of fossil fuels, which release greenhouse gases that trap heat in the atmosphere.
5. Give an example of heat budget in your own view.
Answer: The Earth's heat budget is like a global energy bank account. The Earth receives a deposit of energy from the sun (incoming radiation) and makes withdrawals by radiating heat back into space (outgoing radiation). To maintain a stable climate, the deposits must equal the withdrawals.
6. Mention any two measures to protect Greenhouse effect.
Answer: Two measures to address the greenhouse effect are:
- Reducing fossil fuel consumption by switching to renewable energy sources like solar and wind power.
- Improving energy efficiency at home by using less electricity and better insulation.
7. List any two approaches for solid waste management in your community.
Answer: Two common approaches for solid waste management are:
- Recycling programs, which divert materials like plastics, glass, and paper from landfills.
- Composting organic waste like food scraps and yard trimmings to create nutrient-rich soil and reduce methane emissions from landfills.
8. State any two major toxic chemicals found in environment.
Answer: Two major toxic chemicals found in the environment are lead and mercury, which are heavy metals that can contaminate soil and water.
9. Give an example of chronic toxicity.
Answer: An example of chronic toxicity is the development of lung cancer from prolonged cigarette smoking. The repeated, low-dose exposure to carcinogens over many years leads to a gradual, long-term health effect.
10. Mention the full form of GPS.
Answer: The full form of GPS is Global Positioning System.
11. State the meaning of Remote Sensing(RS).
Answer: Remote sensing is the process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation from a distance, typically using satellites or aircraft.
Group 'B'
12. Illustrate the lentic and lotic environment with examples.
Answer:
13. Briefly describe the various steps of soil profile.
Answer:
Or
Briefly describe the properties of soil.
Answer:
14. What is vegetation sampling method? Explain itstypes.
Answer:
15. Analyze the impacts of climate change in the context of Nepal.
Answer:
16. Interpret the bio- magnificationin eco system with example.
Answer:
17. Explain the technological approaches of pollution control in brief.
Answer:
18. Explain the primary waste watertreatment.
Answer:
19. Mention the various applications of GIS in your daily life.
Answer:
Or
Briefly describe the various units of land measurement system with examples.
Answer:
Group 'C'
20. Describe the vertical zonation of atmosphere. Illustrate the metrological parameters of atmosphereon environment.
Answer:
21. Mention the solid waste management approaches and explain any two approaches of solid waste management at your community.
Answer:
22. Analyze the environmental impact assessment(EIA)system in Nepal.
Answer:
Or
Discuss the various plan and policies being adopted to protect environmental degradation in Nepal.
Answer: