Grade 7 Q&A: Chapter 16: Natural Resources

Concept Questions

Q1: What are natural resources? Give two examples.

Answer: Natural resources are substances or energy forms that occur naturally in the environment and are useful to humans. Examples include sunlight, water, forests, coal, and minerals.

Q2: Differentiate between renewable and non-renewable resources.

Answer:

• Renewable Resources: These can be replenished or renewed naturally over a relatively short period (e.g., sunlight, wind, water, forests). They are considered inexhaustible if managed properly.
• Non-renewable Resources: These exist in finite quantities and cannot be replenished on a human timescale once used up (e.g., fossil fuels like coal and petroleum, minerals like iron and copper).

Q3: Give two examples of renewable resources.

Answer: Two examples of renewable resources are solar energy (sunlight) and wind energy.

Q4: Give two examples of non-renewable resources.

Answer: Two examples of non-renewable resources are coal and petroleum.

Q5: Why is water considered a renewable resource, but also needs to be conserved?

Answer: Water is renewable because it is continuously recycled through the water cycle (evaporation, condensation, precipitation). However, fresh, usable water is limited in many regions and can be depleted or contaminated if not conserved. Overuse and pollution can make it unavailable for human use, despite the natural cycle.

Q6: What are fossil fuels? Name three types.

Answer: Fossil fuels are non-renewable energy resources formed over millions of years from the remains of ancient plants and animals. Three types are coal, petroleum (crude oil), and natural gas.

Q7: Why is conservation of natural resources important?

Answer: Conservation of natural resources is important for several reasons:

• Sustainability: To ensure that resources are available for future generations.
• Environmental Protection: To reduce pollution, habitat destruction, and mitigate climate change.
• Economic Stability: To prevent resource scarcity that can lead to economic crises and conflicts.

Q8: Explain the '4R' principle for natural resource conservation.

Answer: The '4R' principle is a guiding approach for resource conservation:

• Reduce: Minimize the consumption of resources (e.g., use less electricity, reduce water wastage).
• Reuse: Use items multiple times instead of discarding them after a single use (e.g., reuse bottles, bags).
• Recycle: Convert waste materials into new products, reducing the need for virgin raw materials (e.g., recycling paper, glass, metals).
• Refuse: Say 'no' to products that are harmful to the environment or unnecessary, especially single-use items.

Q9: List three ways to conserve water in daily life.

Answer: Three ways to conserve water in daily life are:

1. Repairing leaky pipes and faucets promptly.
2. Using water-efficient appliances (e.g., low-flow showerheads, efficient washing machines).
3. Turning off the tap while brushing teeth or washing dishes.

Q10: What is afforestation? How does it help in forest conservation?

Answer: Afforestation is the process of planting trees in an area where there were no trees previously, or where forests have been removed. It helps in forest conservation by increasing forest cover, which in turn helps prevent soil erosion, maintain biodiversity, regulate climate, and provide raw materials for the future.

Q11: What is sustainable development?

Answer: Sustainable development is development that meets the needs of the present generation without compromising the ability of future generations to meet their own needs. It aims to balance economic growth, social equity, and environmental protection.

Q12: How does proper forest management contribute to sustainability?

Answer: Proper forest management, such as sustainable forestry practices (selective logging, replanting), ensures that forests can continue to provide resources and ecological services (like oxygen production, climate regulation, habitat for wildlife) for a long time without being depleted.

Q13: Why is it important to conserve minerals?

Answer: It is important to conserve minerals because they are non-renewable resources, meaning their supply is finite. Once extracted and used, they are gone forever. Conservation through recycling and finding substitutes helps extend their availability.

Q14: Give two examples of how energy can be conserved.

Answer: Two examples of energy conservation are:

1. Turning off lights and electronic devices when not in use.
2. Using energy-efficient appliances (e.g., LED bulbs, star-rated electronics).

Q15: How does soil conservation benefit the environment?

Answer: Soil conservation benefits the environment by preventing soil erosion, maintaining soil fertility, supporting plant growth, and reducing sediment runoff into water bodies, which protects aquatic ecosystems.

Exercise Solutions (from Page 112)

1. Fill in the blanks:

a. Sunlight and Wind are renewable resources.

b. Coal and petroleum are non-renewable resources.

c. The 4R principle for conservation stands for Reduce, Reuse, Recycle and Refuse.

d. Uranium is a resource used for nuclear energy.

e. Forests help in maintaining the balance of oxygen and carbon dioxide in the atmosphere.

2. Match the pairs:

a. Solar energy - Renewable resource

b. Coal - Non-renewable resource

c. Water cycle - Water conservation

d. Afforestation - Forest conservation

e. Recycling metals - Mineral conservation

3. Answer the following:

a. What are natural resources? Give examples.

Answer: Natural resources are materials or substances such as minerals, forests, water, and fertile land that occur in nature and can be used for economic gain. They are gifts from nature that are essential for human life and development. Examples include sunlight, air, water, soil, forests, wildlife, coal, petroleum, and various minerals like iron and copper.

b. Differentiate between renewable and non-renewable resources.

Answer:

• Renewable Resources: These resources can replenish themselves naturally over a relatively short period of time, often within a human lifetime, and are considered inexhaustible if managed sustainably. Examples include solar energy, wind energy, water (through the water cycle), forests (through replanting), and soil.
• Non-renewable Resources: These resources exist in finite quantities and take millions of years to form. Once consumed, they cannot be replenished on a human timescale, meaning their supply is limited. Examples include fossil fuels (coal, petroleum, natural gas) and most minerals (iron, gold, copper).

c. Why is conservation of natural resources important?

Answer: Conservation of natural resources is crucial for several reasons:

• For Future Generations: It ensures that future generations will also have access to these vital resources for their survival and development.
• Environmental Protection: It helps in preserving ecosystems, reducing pollution, protecting biodiversity, and mitigating climate change.
• Economic Stability: Depletion of resources can lead to scarcity, increased costs, and economic instability. Conservation helps maintain a steady supply.
• Sustainable Living: It promotes a lifestyle that balances human needs with the planet's capacity to provide resources, leading to long-term well-being.

d. Explain the 4R principle with examples.

Answer: The 4R principle is a framework for responsible resource management and waste reduction:

• Reduce: Minimizing the amount of resources consumed and waste generated.
  • Example: Turning off lights and fans when not in use to reduce electricity consumption, or using less water while bathing.
• Reuse: Using items multiple times for their original purpose or a new purpose instead of discarding them after a single use.
  • Example: Using a cloth bag for shopping instead of disposable plastic bags, or reusing glass jars for storage.
• Recycle: Processing used or waste materials into new products to prevent waste of potentially useful materials and reduce the consumption of fresh raw materials.
  • Example: Sending old newspapers, plastic bottles, or aluminum cans to recycling centers to be made into new products.
• Refuse: Declining to buy or use products that are harmful to the environment or are unnecessary, especially single-use items.
  • Example: Refusing a plastic straw at a restaurant, or opting for products with minimal packaging.

e. How can we conserve water?

Answer: We can conserve water in many ways:

• Repairing leaky faucets, pipes, and toilets immediately.
• Taking shorter showers and turning off the tap while lathering or brushing teeth.
• Using water-efficient appliances like low-flow showerheads, efficient washing machines, and dishwashers.
• Collecting rainwater for gardening or other non-potable uses (rainwater harvesting).
• Watering plants in the early morning or late evening to reduce evaporation.
• Avoiding unnecessary flushing of toilets.
• Promoting awareness about water conservation in communities.

f. What is sustainable development?

Answer: Sustainable development is a concept that aims to meet the needs of the present generation without compromising the ability of future generations to meet their own needs. It involves a balanced approach to economic development, social equity, and environmental protection. This means using resources wisely, protecting ecosystems, reducing pollution, and ensuring that everyone has fair access to resources, so that both current and future populations can thrive.

g. Give scientific reasons:

i. We should use public transport.

Answer: We should use public transport because it helps in conserving non-renewable fossil fuels (like petrol and diesel) and reduces air pollution. A single bus or train can carry many passengers, significantly reducing the number of individual vehicles on the road. This leads to lower overall fuel consumption and fewer harmful emissions (carbon dioxide, nitrogen oxides, etc.) per person, contributing to better air quality and mitigating climate change.

ii. We should recycle waste materials.

Answer: We should recycle waste materials because it offers several scientific and environmental benefits. Recycling reduces the demand for new raw materials, which conserves natural resources (e.g., recycling paper saves trees, recycling aluminum saves bauxite ore). It also saves energy, as producing new products from recycled materials often requires less energy than from virgin materials. Furthermore, recycling reduces the amount of waste sent to landfills, decreasing land pollution and the release of greenhouse gases from decomposing waste.

iii. Deforestation is harmful.

Answer: Deforestation is harmful because it has severe negative impacts on the environment and climate. Scientifically, forests play a crucial role in:

• Oxygen Production and Carbon Dioxide Absorption: Trees absorb carbon dioxide and release oxygen, so deforestation contributes to increased atmospheric CO2, a major greenhouse gas, and reduces oxygen supply.
• Soil Conservation: Tree roots hold soil together, preventing erosion by wind and water. Deforestation leads to soil degradation and desertification.
• Water Cycle Regulation: Forests influence rainfall patterns and regulate the water cycle. Their removal can lead to droughts or floods.
• Biodiversity: Forests are home to a vast number of plant and animal species. Deforestation leads to habitat loss and extinction of species.
• Climate Regulation: Forests help regulate global temperatures. Their destruction contributes to global warming.