NCERT Solutions for Class 6 Chapter 11 Nature’s Treasures

👉 Statement 2 is correct. 🌞

🐄 A cow gets energy from the grass it eats, and the grass makes its food using sunlight through photosynthesis. 🌿

So, the cow indirectly gets energy from the Sun by eating plants that store solar energy as food. ☀️➡️🌿➡️🐄

1️⃣ We may have to depend on artificial lighting during daytime also. 💡

2️⃣ Plants will not be able to make food through photosynthesis because they need sunlight to prepare their food. 🌿

3️⃣ The weather will become very cold, and animals and humans may find it difficult to survive due to lack of warmth. ❄️

Cutting down large forest areas is called deforestation. It has many harmful effects:

1️⃣ Loss of habitats for animals 🐘🦜
2️⃣ Increase in carbon dioxide and decrease in oxygen 🌫️
3️⃣ Soil erosion and floods due to lack of tree roots 🌧️
4️⃣ Less rainfall and hotter climate ☀️
5️⃣ Loss of biodiversity — plants and animals may die or disappear ⚠️

✅ Explanation:
🌊 Water and 💨 Wind can be naturally replenished → Renewable.
🌳 Forest regrows through natural processes → Renewable.
🪨 Rock takes millions of years to form → Non-renewable.

(i) ✅ True — Nature provides air, water, sunlight, soil, and minerals that fulfill our basic needs. 🌏

(ii) ❌ False — Machines are man-made resources, created using natural materials. ⚙️

(iii) ✅ True — Natural gas is a non-renewable resource. It cannot be replaced quickly once used; it takes millions of years to form. ⛽

(iv) ✅ True — Air is a renewable resource. It is naturally available and keeps getting renewed through the atmosphere. 💨

(i) A fuel that is commonly used in two-wheelers like scooters or bikes is ___________.
(a) Kerosene
(b) Petrol
(c) Diesel
(d) LPG

✅ Answer: (b) Petrol ⛽
💡 Explanation: Two-wheelers run mainly on petrol engines, which burn fuel to produce energy for movement. 🛵

(ii) An example of a renewable resource is ___________.
(a) Coal
(b) Water
(c) Natural gas
(d) Petrol

✅ Answer: (b) Water 💧
💡 Explanation: Water is a renewable resource because it keeps recycling naturally through the water cycle — evaporation, condensation, and rainfall. 🌦️

• Renewable resources: Forests 🌳
• Non-renewable resources: Coal ⛏️, Natural gas ⛽, Minerals 💎

💡 Explanation: Renewable resources like forests can grow again over time, but coal, natural gas, and minerals take millions of years to form — once used, they’re gone for a long time. ⏳

Petroleum is a non-renewable resource because it takes millions of years to form deep under the Earth’s surface. 🌍
We are using it much faster than nature can produce it. Once exhausted, it cannot be replaced easily.

Regrowing forests takes a very long time because:
1️⃣ Trees need years to grow fully. 🌳
2️⃣ Many animals lose homes, making the ecosystem weak. 🐿️
3️⃣ The soil becomes poor due to erosion after trees are cut. 🌧️

Hence, restoring a forest takes decades — which is why it’s better to protect existing forests. 🌿

1️⃣ Breathing — Air gives oxygen for living beings to survive. 🫁
2️⃣ Flying kites or airplanes — Air helps in lift and movement. 🪁✈️
3️⃣ Burning of fuels — Needs oxygen from air to produce heat. 🔥
4️⃣ Winnowing — Air separates lighter husk from heavier grains. 🌾💨

1️⃣ Plant trees in parks, roadsides, and school campuses. 🌳
2️⃣ Avoid wasting paper — it reduces the need to cut trees. 📚
3️⃣ Join local tree-planting drives or start one with friends. 🤝
4️⃣ Water and protect young plants regularly. 💧
5️⃣ Spread awareness about the importance of greenery. 📢

(i) The type of energy being used for cooking is solar energy. ☀️🍲

(ii) Benefit: Solar energy is renewable and free of cost. It does not cause pollution and helps save fuels like LPG or wood. 🌿
Drawback: It cannot be used on cloudy or rainy days, and cooking takes more time than using regular stoves. ⛅⏳

When trees are cut down, their roots no longer hold the soil firmly. 🌿
As a result, rainwater washes away the top layer of soil, which contains nutrients needed for plant growth. 🌧️
This process is called soil erosion.
Over time, the soil becomes poor in quality, less fertile, and unable to support healthy vegetation. 🌾

🌆 Two Ways Humans Pollute the Air:
1️⃣ Smoke from Vehicles: Cars, buses, and trucks release harmful gases like carbon monoxide and smoke, which pollute the air and cause breathing problems. 🚗💨

2️⃣ Burning of Fuels and Waste: Factories and households burn coal, wood, and garbage, releasing toxic gases and soot into the air. 🏭🔥

🌿 One Action to Reduce Air Pollution:
Plant more trees and protect green areas. 🌳
Trees absorb carbon dioxide and release oxygen, helping to clean the air naturally.

If there were no sunlight for a week —

1️⃣ The solar panels would not work, as they need sunlight to produce electricity. ⚡
2️⃣ The windmill may slow down, because wind movement depends partly on the Sun’s heat and air pressure changes. 💨
3️⃣ Plants would stop making food since they need sunlight for photosynthesis. 🌿
4️⃣ The weather would become cold and dark, and people would need to use artificial lights during the day. 💡

💡 Conclusion: The Sun is the main source of energy on Earth — it helps generate light, wind, and even food energy for all living beings. 🌍☀️

🌿 Report on Tree Cutting and Its Effects
The cutting of trees to build houses or supply wood to industries is not justified if it is done without control or replantation.

Trees are essential for life — they give us oxygen, food, shelter, and rainfall, and help control pollution. 🌱

If trees are cut continuously:
1️⃣ The air becomes polluted as carbon dioxide increases. 🌫️
2️⃣ Soil erosion and floods occur due to loss of roots. 💧
3️⃣ Animals lose their homes, leading to loss of biodiversity. 🐿️
4️⃣ The climate becomes hotter and rainfall decreases. ☀️

However, if trees are cut responsibly, and new trees are planted in place of the old ones, it can be balanced. 🌳

💡 Conclusion:
Tree cutting should be done only when necessary, and planting new trees must always follow.
Protecting trees means protecting life — for us and for future generations. 🌏💚

🌱 My Water-Saving Plan for School

1️⃣ Check for Leaks: Regularly check and repair leaking taps, flushes, or pipes in classrooms and washrooms. 🚰

2️⃣ Use Buckets Instead of Running Taps: During cleaning, use buckets and mugs instead of leaving taps open. 🪣

3️⃣ Install Tap Timers: Fit automatic or push taps that stop water flow quickly to avoid wastage. ⏱️

4️⃣ Rainwater Harvesting: Set up a rainwater collection tank on the school roof to use for gardening and cleaning. 🌧️

5️⃣ Awareness Drive: Start a “Save Water Club” — make posters, perform skits, and spread awareness among students. 🎨📢

🌿 How it Helps the Environment:
• Saves freshwater for future generations. 💧
• Reduces energy use in pumping and purifying water. ⚡
• Helps plants and animals by keeping natural water sources full. 🐸🌾
• Teaches everyone to be responsible global citizens. 🌍