Important Questions Class 6 Social Science Our Past Chapter 2
Class 6 Social Science Chapter 2 Oceans and Continents from the new NCERT textbook Exploring Society: India and Beyond introduces students to the large water bodies and land masses of the Earth. Students learn why the Earth is called the blue planet, how oceans shape climate and support life, how land and water are spread across the hemispheres, and where the five oceans and seven continents are located.
These CBSE important questions for Class 6 Social Science Chapter 2 cover oceans as carbon sinks, the importance of the Pacific Ocean, monsoon rains and tsunamis, the 'water hemisphere', marine life and pollution, and the role of continents in supporting life. Assertion-reason questions and a map question on locating the five major oceans are also included, each with a clear answer in simple English.
CBSE Important Questions Class 6 Social Science Chapter 2 – Oceans and Continents
Q1. Ocean absorbs about one-quarter of the CO2 that we humans create when we burn fossil fuels (oil, coal and natural gas). Examine the relationship between oceans and the carbon cycle. How do oceans act as carbon sinks, and what would be the global impact if oceans could no longer absorb carbon dioxide?
Answer: Oceans play a crucial role in the carbon cycle by absorbing carbon from the atmosphere. They take in about one-quarter of the carbon dioxide (CO2) released by human activities such as burning fossil fuels, which reduces the amount of CO2 in the air.
Oceans act as carbon sinks in two main ways:
• Physical process: CO2 from the air dissolves directly in seawater. Cold water can hold more CO2 than warm water.
• Biological process: tiny marine plants called phytoplankton absorb CO2 during photosynthesis. When they die and sink, the carbon is stored on the ocean floor.
If oceans could no longer absorb CO2, the amount of this greenhouse gas in the atmosphere would rise sharply. This would speed up global warming and climate change, bring more extreme weather, and raise sea levels as ice melts. Higher CO2 would also make the oceans more acidic, harming corals, shellfish and the whole marine food chain.
Q2. Read the source given below and answer the questions that follow.
The Pacific Ocean is the largest ocean on Earth, covering more than one-third of the planet's surface. It supports diverse marine ecosystems and influences global weather patterns. However, its size also makes it vulnerable to issues like plastic pollution and overfishing.
1. Why is the Pacific Ocean significant to global weather systems?
2. How does plastic pollution affect marine ecosystems in the Pacific Ocean?
3. What can individuals do to reduce ocean pollution?
Answer: 1. Because of its huge size, the Pacific Ocean stores a great deal of heat and helps regulate the Earth's temperature. Its currents move warm and cold water around the planet, affecting rainfall, storms and temperatures far away on land.
2. Animals such as turtles, fish and birds mistake plastic for food and choke or starve. Plastic also damages coral reefs and collects into large garbage patches, making it hard for marine life to survive.
3. Individuals can use less plastic, avoid single-use items like straws and bags, recycle, dispose of waste properly and take part in beach clean-ups.
Q3. Read the source given below and answer the questions that follow.
Oceans are the source of many natural phenomena, such as monsoon rains and tsunamis. While oceans bring life-sustaining rain, they can also cause disasters like cyclones and tsunamis. These events often lead to loss of life and damage to coastal regions.
1. How do oceans contribute to rainfall on continents?
2. What causes tsunamis, and why are they dangerous?
3. Describe one method used to reduce the impact of ocean-related natural disasters.
Answer: 1. The Sun heats ocean water, which evaporates into the air as water vapour. The vapour cools to form clouds, which winds carry over the land, where they bring rain. The monsoon rains in India come from the oceans in this way.
2. Tsunamis are caused by underwater earthquakes or volcanic eruptions. They create huge waves that travel very fast and grow taller near the coast, flooding coastal areas, destroying homes and buildings and causing loss of life.
3. Early warning systems help reduce the impact. Tsunami warning systems use sensors such as buoys and seismographs to detect large waves and send alerts to coastal areas, giving people time to move to safer, higher ground.
Q4. Read the source given below and answer the questions that follow.
The Earth's water and land are unevenly distributed across the hemispheres. The Southern Hemisphere has more water compared to land, making it known as the 'water hemisphere.' In contrast, the Northern Hemisphere has more land. This uneven distribution affects climate and biodiversity.
1. What is the major difference between the Northern and Southern Hemispheres in terms of water and land distribution?
2. How does the abundance of water in the Southern Hemisphere impact its climate?
3. Describe how land distribution affects biodiversity.
Answer: 1. The Northern Hemisphere has more land than water, while the Southern Hemisphere has more water than land. That is why the Southern Hemisphere is called the 'water hemisphere'.
2. Water heats up and cools down slowly. The large amount of water in the Southern Hemisphere prevents extreme temperatures, so its climate is milder and more stable.
3. Areas with more land, like the Northern Hemisphere, have many different environments such as forests, deserts and grasslands. These provide homes for a wide variety of plants and animals.
Q5. Read the source given below and answer the questions that follow.
Oceans are home to a wide variety of marine life, including algae, colourful fish, dolphins, and whales. The oceans also regulate the Earth's climate and produce more than half of the world's oxygen. However, human activities such as overfishing and pollution are threatening marine ecosystems.
1. Why are oceans considered the 'lungs of the planet'?
2. What are some human activities that harm marine ecosystems?
3. Suggest one solution to protect marine life from pollution.
Answer: 1. Oceans produce more than half of the world's oxygen. Tiny ocean plants such as algae release oxygen during photosynthesis, which helps all living things breathe.
2. Overfishing reduces fish populations faster than they can recover, and pollution such as plastic waste damages the habitats of marine animals and plants.
3. Reduce plastic use and dispose of waste properly. Recycling and cleaning beaches and water bodies also stop pollution from reaching the oceans.
Q6. Read the source given below and answer the questions that follow.
The Earth is known as the blue planet because approximately 70% of its surface is covered by water. Oceans, the largest water bodies, play a crucial role in shaping the Earth's climate and supporting life. The remaining 30% of the Earth is land, which forms continents. These continents and oceans impact life on Earth significantly.
1. Why is the Earth called the blue planet?
2. How do oceans influence the climate of the Earth?
3. Explain one way continents contribute to supporting life on Earth.
Answer: 1. About 70% of the Earth's surface is covered by water. Seen from space, the large oceans make the Earth look mostly blue.
2. Oceans absorb heat from the Sun and spread it around the globe through ocean currents. This keeps some areas cooler and others warmer and helps create weather patterns such as rain and storms.
3. Continents provide land for plants, animals and humans. Their forests, rivers and fertile soil are essential for growing food, supporting wildlife and building homes and cities.
Q7. How does the Indian Ocean influence India's climate?
Assertion (A): The Indian Ocean affects India's monsoon rains.
Reason (R): Warm winds from the ocean carry moisture to the Indian subcontinent.
(a) Both A and R are correct, and R explains A.
(b) Both A and R are correct, but R does not explain A.
(c) A is correct, but R is wrong.
(d) A is wrong, but R is correct.
Answer: (a) Both A and R are correct, and R explains A.
Moisture-laden winds from the Indian Ocean bring the monsoon rains on which India depends.
Q8. Why is Antarctica known as the coldest continent?
Assertion (A): Antarctica has extreme cold due to its location near the South Pole.
Reason (R): It receives slanted sunlight and is covered with ice.
(a) Both A and R are correct, and R explains A.
(b) Both A and R are correct, but R does not explain A.
(c) A is correct, but R is wrong.
(d) A is wrong, but R is correct.
Answer: (a) Both A and R are correct, and R explains A.
Its position near the South Pole means it gets slanting sunlight, and its ice cover keeps temperatures freezing.
Q9. What makes the Pacific Ocean unique?
Assertion (A): The Pacific Ocean is the largest ocean on Earth.
Reason (R): It contains more freshwater than any other ocean.
(a) Both A and R are correct, and R explains A.
(b) Both A and R are correct, but R does not explain A.
(c) A is correct, but R is wrong.
(d) A is wrong, but R is correct.
Answer: (c) A is correct, but R is wrong.
The Pacific is the largest ocean, but like all oceans it contains saltwater, not freshwater.
Q10. Why is the Earth called the blue planet?
Assertion (A): The Earth is mostly covered by water, giving it a blue appearance from space.
Reason (R): Oceans account for 50% of the Earth's total surface area.
(a) Both A and R are correct, and R explains A.
(b) Both A and R are correct, but R does not explain A.
(c) A is correct, but R is wrong.
(d) A is wrong, but R is correct.
Answer: (c) A is correct, but R is wrong.
Water covers nearly 70% of the Earth's surface, not 50%.
Q11. How do oceans influence the Earth's climate?
Assertion (A): Oceans regulate the Earth's climate by distributing heat through currents.
Reason (R): Ocean currents carry warm and cold water across the globe, balancing temperatures.
(a) Both A and R are correct, and R explains A.
(b) Both A and R are correct, but R does not explain A.
(c) A is correct, but R is wrong.
(d) A is wrong, but R is correct.
Answer: (a) Both A and R are correct, and R explains A.
Ocean currents transfer heat around the Earth, which affects global weather and climate.
Q12. On a world map, locate and label the five major oceans: Atlantic Ocean, Indian Ocean, Pacific Ocean, Arctic Ocean and Southern Ocean.
Answer: • Pacific Ocean: the largest ocean, between the Americas on one side and Asia and Australia on the other.
• Atlantic Ocean: between North and South America to the west and Europe and Africa to the east.
• Indian Ocean: south of Asia, east of Africa and west of Australia.
• Southern Ocean: surrounds the continent of Antarctica.
• Arctic Ocean: the smallest ocean, around the North Pole, surrounded by North America, Europe and Asia.
Related Study Material on Extramarks
- CBSE Important Questions Class 6 Social Science Chapter 1 – Locating Places on the Earth
- CBSE Important Questions Class 6 Social Science Chapter 2 – Oceans and Continents
- CBSE Important Questions Class 6 Social Science Chapter 3 – Landforms and Life
- CBSE Important Questions Class 6 Social Science Chapter 4 – Timeline and Sources of History
- CBSE Important Questions Class 6 Social Science Chapter 5 – India, That Is Bharat
- CBSE Important Questions Class 6 Social Science Chapter 6 – The Beginnings of Indian Civilisation
- CBSE Important Questions Class 6 Social Science Chapter 7 – India's Cultural Roots
Q.1 Many kinds of earthen pots have also been found in the Neolithic age.
1) How were the pots used? (3 marks)
2) What other things can be found in the Neolithic Age? (2 marks)
Marks:1
Ans
1) It seems like the primary function of earthen pots was to store food and grain because agriculture started giving surpluses of grains. However, as agriculture and humans progressed, these same pots were used to prepare food, particularly rice, wheat, and lentils, as evidenced in numerous places. Thus, pots were transformed from being just a storage device to the makers of a very important factor of life: food.
2) Neolithic Age was a diverse phase when people gradually started moving from hunting-gathering to settling and forming civilizations. The other thing that can be found is cotton. Cotton had started to be cultivated and people had started to weave cloth from it, which can be considered a great achievement.
FAQs (Frequently Asked Questions)
In NCERT Class 6 History, Chapter 3, the topic is “From gathering to growing food.” The history of human civilisation’s characteristics and their foraging-related evolution are covered in this chapter on how they transformed from hunting and gathering food to cultivating and growing it. For the students to comprehend the topics, each section is explained in simple words. To get a deeper understanding of the chapter, students can refer to Extramarks Important Questions Class 6 Social Science Our Pasts Chapter 2.
It would be possible to ensure you have understood all the concepts and events by practising all the questions. This would guarantee that you receive high scores and help you identify the areas in which you need to put in more effort and practice. Study and revise the exercises and you will be able to understand every concept and answer any question easily. . Additionally, you will become familiar with the many question formats and types of questions that might be used in exams. This will make you confident and help you master the topic. Students can refer to Extramarks Important Questions Class 6 Social Science Our Pasts Chapter 2 to find all the answers to the exercises.