Major Water Bodies
ICSE Class 6 · Geography · Chapter 4
What this chapter covers
- Oceans of the World
- Seas: Marginal and Inland
- Lakes of the World
- Rivers of the World
- Why Water Bodies Matter
- Pollution of Water Bodies
- Locating Water Bodies on the World Map
Key points
- About three-fourths of the Earth's surface is covered by water.
- The five oceans are the Pacific (largest and deepest), Atlantic, Indian, Southern and Arctic (smallest).
- Marginal seas, such as the Bering, Caribbean, North, Arabian and Red Seas, open freely into an ocean.
- Inland seas, such as the Black, Caspian, Aral and Dead Seas, are almost or fully surrounded by land.
- Important lakes are Baikal, the five Great Lakes, Onega, Titicaca, Victoria and Chilika.
- Important rivers are the Mackenzie, St Lawrence, Mississippi, Amazon, Nile, Rhine, Danube, Indus, Ganga, Yangtze, Huang Ho, Ob and Murray.
- The earliest civilisations grew in river valleys, such as those of the Nile, Indus and Huang Ho.
- Water bodies give water, food, transport, electricity, rain and homes for wildlife.
- Sewage, factory waste, farm chemicals, plastic and oil pollute water bodies and harm life.
Questions answered
Name the five oceans of the world. Which is the largest and which is the smallest?
Pacific, Atlantic, Indian, Southern and Arctic. The Pacific is the largest, and the Arctic is the smallest.
Which is the only ocean named after a country?
The Indian Ocean.
What is the difference between a marginal sea and an inland sea? Give one example of each.
A marginal sea lies at the edge of an ocean and opens freely into it, such as the Arabian Sea. An inland sea is almost or fully surrounded by land, such as the Caspian Sea.
Why can a person float easily in the Dead Sea?
Its water is extremely salty, and very salty water holds up the body more strongly than fresh water.
Name the deepest lake in the world and the country in which it lies.
Lake Baikal, in Russia.
Why is Chilika Lake called a lagoon, and what kind of water does it have?
It is a shallow body of water cut off from the Bay of Bengal by a narrow strip of sand. Its water is brackish, a mix of fresh and salt water.
Name the longest river in the world and the sea into which it flows.
The Nile, which flows into the Mediterranean Sea.
Name the river along which the Indus Valley civilisation grew. Give one reason why early people settled near rivers.
The Indus. Rivers gave them water for drinking and farming, and fertile soil for crops.