Watch the video on the lesson:
Flow ChartI. Features of a desert
1. Very low rainfall
2. Less vegetation
3. Very cold nights
4. Strong winds
5. Dust storms
6. Sand dunes
II. 3 Stages of a river
1. The upper or the young course -
- The river originates here.
- The river flows speedily with less water
- Canyons, waterfalls and rapids are formed
2. Middle or the mature course -
- The river enters the plain.
- The speed of the water decreases.
- The river develops loop called meander.
3. The lower or the old course -
- The river joins a bigger water body.
- The speed of the water is very slow.
- The river is formed by many channels.
- Deltas are formed near the mouth of the river.
Questions & AnswersQ1. How are mountains useful to us?
Ans. Uses of mountains -
- They act as barriers against cold and hot winds.
- Rivers that originate from the mountains provide water for irrigation.
- The slopes of mountains have rich pasture lands and mineral resources.
- The cool climate in summer attracts many tourists.
Q2. Why agriculture cannot be practiced in mountains?
Ans. Agriculture cannot be practiced in mountains because -
- These regions are thinly populated due to unsuitable climate.
- There is shortage of flat land which is required for agriculture.
- Transportation is very difficult.
Q3. Why are plateaus important?
Ans. Importance of plateaus
- Grasslands in the plateaus are widely used to rear cattle and sheep.
- Some older plateaus are rich in mineral resources such as Chota Nagpur Plateau.
- Mining is the important occupation in these regions.
Q4. Why are plains important?
Ans. Importance of plains
- Plains have fertile soil, enough flat land surface for agriculture.
- It is easy to construct roads, railways and aerodromes and canals.
- Most of the ancient civilizations have come up on the banks of rivers in plains.
- Many big cities and towns are located in plains
Tick the correct answer1. About (65 / 71 / 29) percent of the Earth's surface is covered with water.
Ans. 71 percent.
2. The (Himalaya / Aravalli / Deccan) mountains are young mountains.
3. Several (mountains / rivers / valleys) join together to form a chain.
4. The Grand Canyon in the Colorado Plateau is in (India / the U.S.A / Tibet)
Ans. The U.S.A
5. The variation in physical features on the Earth's surface is called
Ans. (d) relief.
6. Agriculture cannot be practiced on mountains on a large scale as they
(a) are thinly populated
(b) have a thin soil cover
(c) have a shortage of land
(d) have an unsuitable climate
Ans. (b) have a thin soil cover
7. Plains are formed by the rivers deposits of
(a) grass and silt
(b) stones and silt
(c) water and silt
(d) sand and silt
Ans. (d) sand and silt
8. Lands that have an arid climate and are barren called
Ans. (d) deserts
9. In the middle stage, the river develops loops called
Ans. (b) meanders
Fill in the blanks1. Land covers about 29 percent of Earth's surface.
2. Plains are also called lowlands.
3. Hills of sand in a desert are known as sand dunes.
4. A river forms deltas in its middle course.