🌍 The Earth and its Living World 🌊
Class 5 - Environmental Studies - Chapter 3
Maharashtra State Board
☀️ Dark patches due to sun's rays are called sunspots.
🍋 Natural care: Apply slices of fresh lemon on it for 10-15 minutes.
🌿 Alternative: Apply aloe vera gel twice a day.
🦠 Microorganisms live in the soil and do the work of decomposing dead plants and animals.
🌾 If there were no microorganisms:
- Dead plants and animals would not get decomposed
- They would have got accumulated
- The soil would not become fertile
✅ So microorganisms help keep our soil healthy and fertile!
🐟 Foods from the Sea:
- 🐠 Fish: Salmon, tuna, mackerel, sardines, pomfret
- 🦐 Shellfish: Prawns, shrimps, crabs, lobsters
- 🦑 Mollusks: Squids, octopus, oysters, mussels
- 🌊 Seaweed: Used in soups, salads, and sushi
- 🧂 Sea salt: Obtained by evaporating sea water
- 🐚 Clams: Rich in protein and minerals
- 🦀 Crabs: Delicious and nutritious seafood
- 🐡 Sea vegetables: Rich in vitamins and minerals
- 💊 Fish oil: Contains omega-3 fatty acids
- 🍣 Caviar: Fish eggs considered a delicacy
☁️ Clouds are made up of very fine droplets of water which are small and light.
🌍 Living things occupy parts of the lithosphere, hydrosphere, and atmosphere. Living things and all the parts they occupy are together called the biosphere.
🏔️ Common Landforms:
- Mountain
- Hill
- Hillock
- Valley
- Plains
- Plateaus
- River
Example Descriptions:
⛰️ Mountain: A mountain is a very high landform that rises high above the surrounding area. It has steep slopes and a peak at the top.
🏞️ Valley: A valley is a low area of land between hills or mountains, often with a river flowing through it.
Anil lives at the foot of a hill.
Ria lives in the plateau region.
Ganga is India's longest river.
Esselworld is situated near the sea shore.
Andaman and Nicobar are beautiful islands.
Agriculture is the main occupation in the plains.
☀️ Evaporation is the process by which water changes from liquid to vapor state.
🌡️ Due to the heat of the sun, the water from the earth's surface goes into vapor state.
💨 This forms fine droplets of water which are small and light.
✨ This process is called evaporation.
❄️ Condensation is the process when vapor turns into water on cooling.
💧 When water vapor cools down, it forms drops of water.
☁️ This process is called condensation.
🔄 The Water Cycle 🔄
☁️ Clouds, 🌧️ Rain, 🌪️ Storm, 🌫️ Fog, 💨 Wind
🏞️ River, 🌊 Lake, 🌧️ Rain, 💧 Well, ⛲ Spring
🌏 Asia, 🌍 Africa, 🌎 North America, 🌏 Europe
🌊 The Atlantic Ocean, 🌊 Pacific Ocean, 🌊 Indian Ocean, 🌊 Arctic Ocean
🐘 Elephant, 🦁 Lions, 🦓 Zebra, 🦒 Giraffe
(a) Water Cycle
Key Labels: ☀️ Sun, ☁️ Cloud, 💧 Condensation, 🌧️ Precipitation, 🌊 Collection, ⬆️ Evaporation
(b) The Earth's Atmosphere
Layers (from bottom to top):
- 🌍 Troposphere (0-13 km) - Weather happens here
- ✈️ Stratosphere (13-50 km) - Contains ozone layer
- 🌠 Mesosphere (50-80 km) - Meteors burn here
- 🛰️ Ionosphere (80-600 km) - Contains charged particles
- 🚀 Exosphere (600+ km) - Merges with space
(c) The Spheres of the Earth
Earth's crust and land
All water on Earth
Air around Earth
All living things
🏖️ The land along the margins of an ocean is called a coastal region.
🏞️ A water body formed by water collecting naturally in a low-lying area of land is called a lake.
💧 The water or ice that occupies the earth's surface, groundwater, and the water vapour in the atmosphere together form the earth's hydrosphere.
The layers of the atmosphere are:
- 1️⃣ Troposphere
- 2️⃣ Stratosphere
- 3️⃣ Mesosphere
- 4️⃣ Ionosphere
- 5️⃣ Exosphere
💨 The atmosphere mainly consists of a mixture of gases:
- 🌬️ Nitrogen
- 💨 Oxygen
- 💧 Water vapour
- 🌿 Carbon dioxide
🌏 A vast continuous stretch of land is called a continent.
The five oceans are:
- 🌊 Atlantic Ocean
- 🌊 Pacific Ocean
- 🌊 Indian Ocean
- 🌊 Arctic Ocean
- 🌊 Southern Ocean
❄️ Water particles in the cloud freeze, and in the cold regions, they come down in the form of snow.
🧊 Huge blocks or mass of ice floating in the sea are called icebergs.
💧 There is a lot of water stored in the underground layers of rock. This water is called groundwater.
🛡️ In the lower part of the stratosphere, there is a layer of a gas called ozone.
☀️ Ultraviolet rays coming from the sun are harmful for living things.
🛡️ But the ozone layer absorbs them and protects the living world from those harmful rays.
🦘 Kangaroos are found only in Australia.
🐻❄️ Polar bears are seen only in the snowbound polar regions.
🏔️ Glacier:
- ❄️ In cold regions, when layers of snow pile up on the ground, they form ice.
- 🧊 When such layers of ice pile up in a low-lying area, they become enormous in size.
- ⬇️ This huge mass slips down a slope at a very slow speed.
- 🏔️ This is called a glacier.
☁️ Troposphere:
- 🌍 The layer of air that extends from the earth's surface to a height of about 13 km is called the troposphere.
- 🌡️ The conditions in the troposphere change continuously.
- 🌬️ As this layer touches the surface of the earth, the living world gets greatly affected.
- ❄️ As we go higher in the troposphere, the air gets cooler and rarer.
- 💧 Almost all the water vapour in the atmosphere is contained in the troposphere.
- 🌧️ That is why, all weather-related phenomena such as formation of clouds, rain, fog, winds, and storms take place in the troposphere.
🌧️ How Rain Forms 🌧️
✈️ Stratosphere:
- 🌍 Beyond the troposphere, up to a height of about 50 km from the earth is the layer called the stratosphere.
- 🛡️ In the lower part of the stratosphere, there is a layer of gas called ozone.
- ☀️ Ultraviolet rays coming from the sun are harmful for living things.
- ✅ But the ozone layer absorbs them and protects the living world from those harmful rays.
- ☀️ The surface of the earth gets heated due to the heat of the sun.
- 🌡️ So, the air near the surface is the hottest.
- ❄️ Therefore, as we go higher in the troposphere, it becomes cooler.
- 💧 Almost all water vapour in the atmosphere is present in the troposphere.
- 🌧️ Therefore, all weather-related phenomena take place in the troposphere.
- ☁️ This includes clouds, rain, fog, winds, and storms.
- 🏔️ As we go higher from the surface of the earth, the air in the atmosphere becomes rarer.
- 💨 This means there is less oxygen available at high altitudes.
- 🧗 Therefore, mountaineers carry oxygen in cylinders when they climb mountains that are more than 5000 m high to get sufficient supply of oxygen.
🌍 Earth is the only planet with liquid water on its surface!
🌊 About 71% of Earth's surface is covered with water!
🏔️ Mount Everest is the highest mountain at 8,848 meters!
🌊 The Pacific Ocean is the largest ocean on Earth!
🦘 Each continent has unique animals - like kangaroos in Australia!
💨 We live in the troposphere - the lowest layer of atmosphere!
🛡️ The ozone layer protects us from harmful UV rays!
🔄 The water cycle is continuous and never stops!
| Feature | Lithosphere 🪨 | Hydrosphere 💧 | Atmosphere 💨 |
|---|---|---|---|
| What is it? | Earth's crust and land | All water on Earth | Air around Earth |
| Examples | Mountains, plains, valleys | Oceans, rivers, lakes | Oxygen, nitrogen, clouds |
| Importance | Where we live and grow food | Essential for all life | We breathe air to live |
Key Concepts We Learned:
- 🌍 Earth has three main spheres: Lithosphere (land), Hydrosphere (water), Atmosphere (air)
- 🌱 Biosphere: All living things on Earth occupy parts of all three spheres
- 🌏 Seven Continents: Asia (largest), Africa, North America, South America, Europe, Antarctica, Australia (smallest)
- 🌊 Five Oceans: Pacific, Atlantic, Indian, Arctic, Southern
- 🔄 Water Cycle: Evaporation → Condensation → Precipitation → Collection
- ☁️ Troposphere: Closest layer where weather happens
- 🛡️ Ozone Layer: Protects us from harmful UV rays
- 🦠 Microorganisms: Help decompose dead matter and keep soil fertile
- 🏔️ Landforms: Mountains, valleys, plains, plateaus, rivers, etc.
- 🐘 Different Animals: Live in different regions based on climate
✅ Draw diagrams of the water cycle and atmosphere layers
✅ Make flashcards for continents and oceans
✅ Remember: Asia is largest continent, Australia is smallest
✅ Practice explaining the importance of microorganisms
✅ Understand how clouds form and cause rain
✅ Learn about the ozone layer and its importance
