Oceans and Life
Class 6 Social Science · Chapter 2: Oceans and Continents · NCERT Exploring Society: India and Beyond section 2.4
Learn
Life on Earth began in the oceans, and they are still full of life: from tiny plankton to the giant blue whale, the largest animal that has ever lived. Coral reefs are colourful underwater homes for thousands of kinds of fish and other creatures.
Oceans keep Earth's climate gentle by storing heat. Tiny ocean plants (algae) make a large share of the oxygen we breathe. Oceans give us fish and salt, and ships carry most of the world's trade across them.
People harm the oceans by dumping plastic, spilling oil and overfishing, catching fish faster than they can breed. In India, fishing is paused for some weeks during the monsoon so that fish can breed.
Neel and his friends join a beach clean-up and fill twenty bags with plastic in one morning. Small actions, like carrying a cloth bag and never throwing litter near water, help keep the oceans healthy.
Explore: helps or harms the ocean?
- Sort each action.
Remember
- Oceans are full of life and give us food, oxygen, trade routes and a gentle climate.
- Plastic, oil spills and overfishing harm the oceans; small actions can help protect them.
Quick check
Why is overfishing harmful?
- Fish are caught faster than they can breed
- It makes the ocean bigger
- It cleans the water
- It helps coral grow
Answer
Fish are caught faster than they can breed. Then fish numbers fall and people who depend on fishing suffer too.
Think about it
Why might fishing communities support a fishing break during the monsoon?
One answer
It lets fish breed so there are enough fish in future years. Their livelihood depends on the ocean staying healthy.
Practice
Practise with fresh questions at three levels (easy, medium, hard), some answered hands-on, with hints and worked answers. Get 4 of your last 5 right to finish the topic.