The Earth and its Living World - Standard 5 - Environmental Studies - Part 1 - Balbharati
The Earth and its Living World
Q.1 What’s the solution ?
Dark patches appear on the skin after exposure to the sun.
Ans. When you spend time in the sun, dark patches can appear on your skin. This happens because your skin produces more pigment called melanin to protect itself from the sun's harmful rays. This extra melanin can cause uneven dark spots on your skin. It's important to protect your skin from excessive sun exposure to prevent these dark patches from forming.
Q.2 Use your brain power !
(a) Why are micro-organisms important ?
Ans. Microorganisms are important because they help with recycling nutrients in nature, making food, fighting diseases, and cleaning up pollution. They break down dead plants and animals, which releases nutrients back into the environment. Some microorganisms are used to make delicious foods like cheese and yogurt. They also produce medicines to help us fight off infections. In addition, they can clean up harmful substances in the environment. So, microorganisms are tiny but they have big roles in keeping things balanced and healthy.
(b) Think about all the foodstuffs obtained from the sea. Find more information and write ten lines about them.
Ans. 1. Fish: Fish is a yummy and healthy food from the sea.
2. Shrimp: Shrimp is a tasty seafood that is good for you and low in calories.
3. Lobster: Lobster is a special seafood with sweet meat that has important nutrients.
4. Crab: Crab meat is delicious and gives you energy with vitamins and minerals.
5. Oysters: Oysters are a fancy treat from the sea, full of nutrients like iron and vitamin B12.
6. Mussels: Mussels are small shellfish that are good for you and have vitamins and minerals.
7. Seaweed: Seaweed is a nutritious plant from the sea that can be yummy in salads and sushi.
8. Calamari: Calamari, or squid, is a soft and tasty seafood that has good things for your body.
9. Tuna: Tuna is a popular fish that is healthy for you and has special oils that are good for your brain.
10. Scallops: Scallops are small shellfish that taste sweet and have vitamins and minerals that help your body.
These foods from the sea are not only delicious but also provide important nutrients to help you stay healthy.
Q.3 Answer the following questions.
(a) What are clouds made of ?
Ans. Clouds are made up of water vapour.
(b) What is meant by ‘biosphere’ ?
Ans. Living things exist in the lithosphere, hydrosphere and atmosphere. They also interact with these spheres. This living world constitutes the biosphere.
(c) Make a list of the landforms you see in your surroundings and give a description of any two of them.
Ans. [Students should write their own answer]
Q.4 In the following sentences, underline the words that refer to landforms.
(a) Anil lives at the foot of a hill.
Ans. Hill.
(b) Ria lives in the plateau region.
Ans. Plateau.
Q.5 Write a note about the following.
(a) Evaporation: Evaporation is when water turns into a gas called water vapour because of the sun's heat. It helps water go from the ground or oceans into the air. This vapor later turns into clouds and then falls back to the ground as rain or snow, so we have water again. Evaporation also cools things down and helps move heat around in the air. It's an important part of how water moves and affects the weather.
(b) Condensation: Condensation is when water vapour in the air cools down and becomes liquid water. It forms clouds and helps bring rain. It's an important part of the water cycle that brings water back to the Earth's surface.
(c) The water cycle:
1. Water on the earth evaporates continuously due to the heat of the sun. Water that has percolated into the soil also evaporates due to the heat and enters the atmosphere.
2. As water vapour is lighter than air, it rises high up into the atmosphere. As it goes higher, it cools and condenses forming very fine droplets of water. The droplets are so small and light that they float in the atmosphere forming clouds. These small droplets join together and form bigger drops which are heavy. They cannot float. Such drops of water fall down on the earth in the form of rain.
3. This rainwater flows into rills, streams, rivers and finally into the sea. Ice in the snow-covered regions also melts due to the heat of the sun to finally flow into rivers.
4. These processes of evaporation, condensation and rainfall go on in a continuous cycle. This is known as the water cycle in nature.
Q.6 Give two examples of each.
(a) Weather-related events: Rainfall, Snowfall.
(b) Sources of water: Well, River.
Q.7 Draw a labelled diagram showing the water cycle.
Ans.
