1. Water—The Essence of Life
Answers to all Write, Discuss, Find out, Activity and Let us reflect questions. NCERT Our Wondrous World, Class 5 EVS (CBSE) · Unit 1: Life Around Us.
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Discuss
No. Ocean water is very salty. It is not fit for drinking.
- To make salt (as in the salt pans of Gujarat).
- For ships and boats to travel and carry goods.
- For fishing.
- As a home for sea plants and animals.
Activity 1
The pictures show: Pond, Sea, Glacier (ice), Snow-covered mountains, Groundwater, River, Well and Rain.
The sea is a source of water, but its water is salty. All the others give us freshwater.
Activity 2
They come from the water vapour in the air. The vapour touches the cold glass. It cools and turns into tiny droplets.
The ice cubes melt and turn into water.
The water becomes hot and starts boiling. It slowly turns into steam (water vapour).
We see all three forms of water — solid (ice), liquid (water) and vapour (steam).
| Activity | I Observe |
|---|---|
| Ice melting | Solid ice changes into liquid water. |
| Water boiling | Water bubbles and changes into steam (vapour). |
| Water in sunlight for three days | The water level goes down. Water slowly changes into vapour. |
Activity 3
| I Observe | I Wonder | It is because of … |
|---|---|---|
| Water heats up | How does water heat up? | Sunlight |
| Water droplets formed inside the cover | Where do these droplets come from? | Water vapour cools and turns into droplets. |
| Droplets slide down to the water | Why do the droplets fall down? | Droplets join and become heavy, like rain. |
Activity 4
The water soaks into the soil. It sinks down slowly through the gaps in the soil. The soil becomes wet and some water collects at the bottom.
Activity 5
Green lawn ✔
Rainwater can soak into the soil of a green lawn. Concrete roads and paved areas do not let water go into the ground.
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Activity 6
The seeds rolled down from the highest point along the slopes of the paper.
They do not move in a straight line. They spread out in different directions, following the slopes.
Yes. The seeds collect in the low places and folds. This is just like water gathering in lakes and rivers.
Discuss
Water always flows from higher land to lower land, like the mustard seeds.
The Western Ghats are high and close to the west coast. So rivers starting there, like Godavari, Krishna and Kaveri, flow down towards the east into the Bay of Bengal.
Narmada and Tapi flow through valleys that slope towards the west. So they fall into the Arabian Sea.
Activity 7
| Name of the River | Moves towards the Bay of Bengal | Moves towards the Arabian Sea |
|---|---|---|
| Ganga | ✔ | |
| Yamuna (joins Ganga) | ✔ | |
| Brahmaputra | ✔ | |
| Godavari | ✔ | |
| Krishna | ✔ | |
| Kaveri | ✔ | |
| Narmada | ✔ | |
| Tapi (Tapti) | ✔ |
Life in Water
| Animals on Land | Animals in Water |
|---|---|
| Cannot breathe in water. | Have fins to swim. |
| Breathe air through the nose and lungs. | Fish breathe in water through gills. |
| Have legs to walk, run or jump. | Have a smooth, boat-shaped body to move in water. |
| Body is covered with skin, hair or fur. | Fish have scales on the body. |
| Live in nests, burrows, dens or houses. | Live in ponds, rivers, lakes or seas. |
Activity 8
| Bird or Animal | Mouth or Beak | Movement through Legs, Feet, Fins |
|---|---|---|
| Fish | Round mouth facing upwards | Fins |
| Pond heron | Long and pointed | Thin legs |
| Duck | Flat and broad beak | Webbed feet |
| Frog | Wide mouth | Strong back legs with webbed feet |
| Turtle | Hard, beak-like mouth | Flippers (flat legs) |
| Water snake | Wide mouth | No legs; moves by wriggling its body |
Draw a rough diagram of each animal in your notebook. Your table may have other animals you saw.
| Types | Names | Local Name (Hindi) |
|---|---|---|
| Plants floating (above water) | Lily, Water hyacinth, Duckweed | Kumudini, Jalkumbhi |
| Plants under water | Hydrilla, Eelgrass (Vallisneria) | — |
| Roots in the water bed, but seen above the water | Lotus | Kamal |
Write the local names used in your own language.
Activity 9
On plain paper, the drop soaks in and the paper becomes wet.
On the waxed paper, the drop does not soak in. It stays like a round bead and rolls off. Wax keeps water out.
Activity 10
A simple river food chain:
If all the fish are gone, animals that eat fish will not get food. Birds, otters and crocodiles may die or leave the river. Small water plants and insects may grow too much. The whole chain gets disturbed.
Let us reflect
| Column A | Column B |
|---|---|
| (i) Ocean water | (c) Not fit for drinking |
| (ii) Snow | (a) Solid form of water |
| (iii) Steam | (b) Vapour form of water |
| (iv) Rainwater | (d) Freshwater |
Most of the water on Earth is in the oceans. It is very salty. Salty water is harmful to drink and damages crops. Some freshwater is also frozen as ice.
All living beings need water to live. Water bodies give them water to drink, food to eat and a place to live.
- Wells, ponds and rivers would dry up.
- Groundwater level would go down.
- Crops would fail and there would be less food.
- People and animals would not get enough drinking water.
- Many people may have to leave their homes.
In a forest, trees and soft soil soak up rainwater. The water goes underground and recharges groundwater.
In a city, cement roads and buildings do not let water soak in. The water flows into drains. It can cause floods, and groundwater is not recharged.
- Rooftop rainwater harvesting with a storage tank.
- A recharge pit or soak pit to send rainwater underground.
- Taps that close on their own and no leaking pipes.
- Reusing water from washing vegetables for plants.
- Open green areas instead of cement everywhere.
This is a paper-folding activity. Follow the steps in the textbook.