1. John noticed that the river near his house had turned dark and smelled bad. What could be the possible cause of this change in the river?
a) Cutting down of trees near the river trees
b) Fishing in the river
c) Dumping industrial waste into the river
d) Building new houses near the river
Answer: c) Industrial waste contains harmful chemicals that can pollute the water, causing it to turn dark and smell bad. This is why it's important to properly dispose of industrial waste to protect our rivers and the environment.
2. How does water pollution affect aquatic life?
a) It improves the health of aquatic organisms
b) It disrupts food chains and can harm aquatic organisms
c) It has no impact on aquatic organisms
d) It leads to an increase in biodiversity
Answer: b) Pollutants in the water can harm or kill aquatic organisms, including fish, plants, and other organisms that depend on clean water for survival. This can disrupt the food chain.
3. An experiment was conducted to purify water using filtration. What does filtration help in removing?
a) Harmful bacteria
b) Unpleasant taste
c) Foul smell
d) Suspended particles
Answer: d) Filtration helps in removing suspended particles from water. It helps to separate solid particles and impurities, such as dirt and debris, from the water, making it cleaner and clearer to drink.
4. How can you contribute to controlling air pollution in your neighbourhood?
a) By planting trees and creating green spaces
b) By burning waste materials in your backyard
c) By using chemical fertilisers in your garden
d) By driving a car instead of using public transport
Answer: a) Planting trees helps to reduce air pollution by absorbing carbon dioxide and releasing oxygen. Trees act as natural filters, removing pollutants from the air and improving their quality.
5. A city wants to reduce soil pollution. Which of the following actions would be most effective?
a) Encouraging residents to burn their garbage
b) Establishing proper waste disposal systems
c) Dumping garbage near residential areas
d) Using chemical fertilizers extensively
Answer: b) Establishing proper waste disposal systems is the most effective action to reduce soil pollution. It ensures that garbage is disposed of in a controlled and environsciencely-friendly manner, preventing it from contaminating the soil.
