Major Domains of the Earth – Key Points | Class 6 Geography Chapter 5 (JKBOSE/NCERT)
Major Domains of the Earth is an important chapter in Class 6 Geography that introduces students to the four main domains of our planet — Lithosphere, Hydrosphere, Atmosphere, and Biosphere. This chapter explains how land, water, air, and living organisms are closely connected and support life on Earth.
In this post, you will find important key points for JKBOSE/NCERT Chapter 5, written in simple language for quick understanding and easy memorization. These notes are ideal for revision, exams, and concept clarity. Students can read online or download free quality content to make learning Geography simple, effective, and enjoyable.
Key Points – Major Domains of the Earth
The four major domains of the Earth are:
- Lithosphere
- Hydrosphere
- Atmosphere
- Biosphere
Lithosphere
The solid portion of the Earth is called the Lithosphere.
- It consists of the Earth’s crust, rocks, and soil.
- The thin layer of soil contains nutrient elements that support plants and other organisms.
Hydrosphere
The Hydrosphere includes water in all its forms, such as:
- Ice
- Liquid water
- Water vapour
Important facts:
- About 71% of the Earth’s surface is covered with water.
- Around 97% of Earth's water is found in the oceans and is salty.
- Only about 2.5–3% is freshwater.
- Most freshwater is stored in glaciers, ice caps, or underground, leaving less than 1% easily available for human use.
Atmosphere
The Atmosphere is the layer of gases surrounding the Earth.
- It extends up to about 1,600 kilometres above the Earth’s surface.
- It protects us from the harmful rays of the Sun.
- It provides the air necessary for breathing.
Layers of the Atmosphere
The atmosphere is divided into five layers:
- Troposphere
- Stratosphere
- Mesosphere
- Thermosphere
- Exosphere
Composition of Air
Clean, dry air mainly contains:
- Nitrogen – 78%
- Oxygen – 21%
- Other gases (Carbon dioxide, Argon, etc.) – 1%
Biosphere
The Biosphere is the narrow zone where land, water, and air interact.
- It is the region where all living organisms exist.
- It includes plants, animals, and humans.
Main Divisions of the Earth’s Surface
The Earth’s surface is divided into:
- Continents (large landmasses)
- Ocean basins (large water bodies)
Important points:
- All the oceans of the world are connected to each other.
- The sea level is considered zero level for measuring land elevation.
Examples:
- Mount Everest – Highest peak: 8,848 metres above sea level.
- Mariana Trench – Deepest point on Earth: 11,022 metres below sea level.
Continents
There are seven major continents on Earth:
- Asia
- Europe
- Africa
- North America
- South America
- Australia
- Antarctica
Most of the Earth’s landmass lies in the Northern Hemisphere.
Asia
- Largest continent in the world.
- Covers about one-third of Earth’s total land area.
- Located mainly in the Eastern Hemisphere.
- The Tropic of Cancer passes through Asia.
The combined landmass of Europe and Asia is called Eurasia.
Europe
- Smaller than Asia.
- Located west of Asia.
- The Arctic Circle passes through Europe.
- Surrounded by water bodies on three sides.
Africa
- Second largest continent after Asia.
- The Equator passes almost through the middle.
- Only continent through which the Tropic of Cancer, Equator, and Tropic of Capricorn pass.
- Home to the Sahara Desert, the largest hot desert in the world.
- The Nile River, the world’s longest river, flows through Africa.
North America
- Third largest continent.
- Connected to South America by the Isthmus of Panama.
- Located completely in the Northern and Western Hemispheres.
South America
- Mostly located in the Southern Hemisphere.
- The Andes Mountains, the world’s longest mountain range, run from north to south.
- The Amazon River, the largest river by volume, flows here.
Australia
- Smallest continent.
- Lies completely in the Southern Hemisphere.
- Surrounded by oceans and seas.
- Known as the Island Continent.
Antarctica
- Located entirely in the Southern Hemisphere.
- The South Pole lies almost at the centre.
- Covered with thick ice sheets throughout the year.
- There are no permanent human settlements.
India has research stations here:
- Maitri
- Dakshin Gangotri
Oceans
Oceans form the largest part of the Hydrosphere.
- All oceans are interconnected.
- Ocean water is constantly moving.
Main Movements of Ocean Water
- Waves
- Tides
- Ocean Currents
Five Major Oceans
The five major oceans of the world are:
- Pacific Ocean
- Atlantic Ocean
- Indian Ocean
- Southern Ocean
- Arctic Ocean
Pacific Ocean
- Largest ocean in the world.
- Covers about one-third of the Earth’s surface.
- Contains the Mariana Trench, the deepest part of the Earth.
- Surrounded by Asia, Australia, North America, and South America.
Atlantic Ocean
- Second largest ocean.
- S-shaped in appearance.
- Bordered by North and South America on the west and Europe and Africa on the east.
- Its irregular coastline provides good natural harbours.
Indian Ocean
- Named after the country India.
- Triangular in shape.
Bounded by:
- Asia in the north
- Africa in the west
- Australia in the east
Southern Ocean
- Surrounds the continent of Antarctica.
- Extends northward to 60° South latitude.
Arctic Ocean
- Located within the Arctic Circle.
- Surrounds the North Pole.
- Connected to the Pacific Ocean through the Bering Strait.
- Bordered by the northern coasts of North America and Eurasia.
✅ Quick Revision Trick
Remember the four domains easily:
L H A B
- L – Lithosphere
- H – Hydrosphere
- A – Atmosphere
- B – Biosphere
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