Class 6 Social Science
Chapter 2 - Oceans and Continents
Q1. What are oceans and continents? What are their names and their distribution?
Ans: Oceans are vast bodies of saltwater that cover about 71% of the Earth's surface, while
continents are large landmasses that form the Earth's land area. There are five major
oceans and seven continents.
● Oceans: Pacific, Atlantic, Indian, Southern, and Arctic.
● Continents: Asia, Africa, North America, South America, Antarctica, Europe, and
Australia.
These oceans and continents are distributed across the Earth’s surface, with oceans
surrounding and separating the continents.
Q2. In what ways do oceans and continents impact life on Earth, including human life?
Ans: Oceans regulate Earth's climate,support marine life, and provide resources such as fish
and salt. They also serve as major transportation routes for global trade. Continents provide
habitats for humans, plants, and animals, and contain natural resources like minerals,
forests, and freshwater. Together, oceans and continents shape ecosystems, weather
patterns, and
human activities like agriculture, trade, and urban development.
Q3. What are the circular lines in each map called? And do you know what the lines
radiating out of the two poles are called?
Ans: The circular lines on the map are called parallels of latitude, which run parallel to the
equator. The lines radiating out from the poles are known as meridians of longitude. They
help in identifying the exact location of places on Earth.
Q4. Which hemisphere holds more water?
Ans: The Southern Hemisphere holds more water, as it has a greater area covered by
oceans compared to the Northern Hemisphere.
Q5. What do you think could be the approximate proportion of water to land in the
Northern Hemisphere? And in the Southern Hemisphere?
Ans: In the Northern Hemisphere, the proportion of water to land is approximately 60% water
and 40% land. In the Southern Hemisphere, the proportion is around 80% water and 20%
land.
Q6. Are all the oceans connected with one another, or are there separations between
them?
Ans: Yes, all the oceans are connected to one another, forming a global oceanic system.
However, they are traditionally divided into separate oceans based on geographical and
historical distinctions.
Q7. If there is such an abundance of water on the planet, why is there so much talk of
‘Water scarcity’ or a ‘Water crisis’?
Ans: Even though Earth has a vast amount of water, most of it is saltwater in oceans and not
suitable for drinking or agriculture. Only a small portion of the Earth's water is freshwater,
and much of that is locked in glaciers or underground. Factors such as pollution, overuse,
climate change, and unequal distribution of water resources contribute to water scarcity in
many regions, creating a ‘water crisis.’
Q8.What ways of saving water are you aware of? Which ones have you seen practiced at
home, at your school, and in your village, town or city?
Ans: Some ways to save water include:
● At home: Turning off taps when not in use, using buckets instead of hoses for washing,
fixing leaks promptly.
● At school: Installing water-saving devices, ensuring taps are closed properly, and
rainwater harvesting.
● In towns or cities: Rainwater harvesting, water recycling, using efficient irrigation methods
like drip irrigation in agriculture, and public awareness campaigns to reduce
water wastage.
Q9. Explain the following terms:
(a) Continent:
Ans: A continent is a large, continuous landmass that forms a major part of the Earth's
surface. There are seven continents on Earth: Asia, Africa, North America, South America,
Antarctica, Europe, and Australia. These land masses vary in size and are home to different
countries, cultures, and ecosystems.
(b) Ocean:
Ans: An ocean is a vast body of salt water that covers about 71% of the Earth's surface.
Oceans are interconnected and play a crucial role in regulating the Earth's climate,
supporting marine life, and providing resources like fish and minerals. The five major oceans
are the Pacific, Atlantic, Indian, Southern, and Arctic.
(c) Island:
Ans: An island is a landmass that is completely surrounded by water. Islands can vary in
size from small patches of land to large areas like Greenland. Some islands are formed by
volcanic activity, while others may be the result of rising sea levels or erosion. Examples
include Madagascar and the Hawaiian Islands.
Q10. What are the challenges faced by marine environments, and what actions are
necessary for their protection?
Ans: Marine environments face challenges such as pollution from plastic waste and
chemicals, overfishing, and habitat destruction. Protecting them requires reducing pollution,
sustainable fishing practices, international cooperation, and raising awareness about marine
conservation.
Q11. How are continents counted differently, and which count is most widely adopted?
Ans: Continents can be counted as four, five, six, or seven based on different criteria, but the
most widely adopted count is seven continents: Africa, Antarctica, Asia, Australia, Europe,
North America, and South America.
Q12. What is a Tsunami?
Ans: A Tsunami is a natural disaster that originates in the ocean. It is a huge and powerful
wave generally caused by a strong earthquake or a volcanic eruption at the bottom of the
ocean. Tsunamis can travel thousands of kilometres and submerge coastal areas, causing
widespread damage.
Q13. Why is Earth called a Blue Planet?
Ans: When seen from outer space, the Earth appears mostly blue because of the presence
of water on the earth.
Q14. Explain the impact and aftermath of the 2004 Indian Ocean tsunami on India.
Ans: The 2004 Indian Ocean tsunami, caused by an earthquake in Indonesia on 26
December 2004, had a devastating impact on India. Over two lakh people lost their lives
across the affected regions. In India, the Andaman and Nicobar Islands, along with the
coasts of Tamil Nadu and Kerala, were severely affected, suffering significant damage and
loss of life.
The disaster highlighted the need for effective early warning systems and disaster
management. Consequently, many countries, including India, now collaborate in early
warning systems like the Indian Ocean Tsunami Warning System to protect lives and
property from future tsunamis.
