8th Social Science Guide Geography Unit 7 Exploring Continents – Africa Australia and Antarctica
8th Standard Social Science Guide Geography Lesson 7 Exploring Continents – Africa Australia and Antarctica
8th Standard Social Science Guide Unit 7 Exploring Continents – Africa Australia and Antarctica English Medium Guide Book Back Question and answers download pdf. 8th STD All Subject Guide. Tamil Nadu Start Board Syllabus Samacheer kalvi 8th std all Lesson / Units question and answers. 8th Social Science TEXT Books download pdf. Tamil and English Text books. 8th Standard Tamil Guide.
8th Social Science Guide Geography Unit 7 Exploring Continents – Africa Australia and Antarctica
I. Choose the correct answer
1. The southernmost tip of Africa is.
- Cape Blanca
- Cape Agulhas
- Cape of Good Hope
- Cape Town
Ans : Cape of Good Hope
2. The man made canal through an isthmus between Egypt and Sinai Peninsula is
- Panama Canal
- Aswan Canal
- Suez Canal
- Albert Canel
Ans : Suez Canal
3. In respect of the Mediterranean climate, consider the following statements, and choose the correct answer.
1) The average rainfall is 15 cm 2) The summers are hot and dry, winters are rainy.
3) Winters are cool and dry, Summers are hot and wet 4) Citrus fruits are grown
- 1 is correct
- 2 and 4 are correct
- 3 and 4 are correct
- All are correct
Ans : 2 and 4 are correct
4. The range which separates the west and east flowing rivers in Australia is
- Great Dividing Range
- Himalayan Range
- Flinders range
- Mac Donnell Range
Ans : Great Dividing Range
5. Kalgoorile is famous for ………. mining.
- Diamond
- Platinum
- Silver
- Gold
Ans : Gold
II. Fill in the Blanks.
- Atlas Mountain is located in ………………. continentAns : African
- ………………. is the highest peak of Africa.Ans : Mt. Kilimanjaro
- ………………. is the most common tree in Australia.Ans : Eucalyptus
- A temperate grass land of Australia is called ………………. .Ans : Downs
- ………………. is the first Indian research station in Antarctica.Ans : Dakshi Gangotri
III Match the following.
- Pinnacle – Equatorial forest
- Kril – Salt lake
- Ostrich – Small red fish
- Lake Eyre – flightless bird
- Jewel of the earth – pointed limestone pillars
Ans : 1 – E, 2 – C, 3 – D, 4 – B, 5 – A
IV. Let us learn.
1. Assertion (A) : Aurora is a curtain of colour lights appear in the sky.
Reason (R) : They are caused by magnetic storms in the upper atmosphere.
- Both A and R are individually true and R is the correct explanation of A.
- Both A and R are individually true but R is not the correct explanation for A.
- A is true but R is false.
- R is true but A is false
Ans : Both A and R are individually true and R is the correct explanation of A.
2. Assertion (A) : A geological feature of Africa is the Great Rift Valley.
Reason (R) : A Rift valley is a large crack in the earth’s surface formed by tectonic activity.
- Both A and R is individually true and R is the correct explanation for A.
- Both A and R are individually true but R is not the correct explanation for A.
- A is true but R is false.
- R is true but, A is false.
Ans : Both A and R is individually true and R is the correct explanation for A
V. Answer in brief.
1. Why Africa is called a “Mother Continent”?
- Africa is called a Mother continent.
- Because it was the oldest inhabited continent on Earth.
- The diverse geographical condition is the main reason for hetrogeneous culture and home for ethinic groups.
2. What are the important rivers of Africa?
- River Nile – father of African rivers.
- River Congo or Zaire – the second largest river.
- River Niger – Major river.
- River Zambezi – fourth largest river and River of life.
3. Name the physical division of Australia.
- The Great Western Plateau
- The Central Law lands
- The Eastern High lands.
4. Write about the nature of Antarctic continent.
- Antartica is the southern most and fifth largest continent in the world.
- As it is located in polar regions it is coldest continent with a permanent cover of ice.
- Its landform consists of mountain, peaks, valleys, glaciers and plateau.
5. Mention any four economic activities of Australia.
Agriculture, forestry, fishing mining are some economic activity of Australia.
VI. Distinguish the following.
1. Sahel and Sahara
Sahel |
Sahara |
1. Sahel means border or margin |
Largest hot desert in the world |
2. It is largely a semi – acid belt of barren, Sandy and rocky land. |
It covers the area of 11 countries |
3. This region marks the physical and cultural transition. |
Mt. Koussi, an extinct valcano in chad is the highest point in Sahara. |
2. Western Antartica and Eastern Antarctica.
Western Antartica |
Eastern Antarctica |
1. Faces the Pacific Ocean. |
Faces the Altantic and Indian Ocean. |
2. Antartica Penninsula which points towards the South America show that it is the continuation of the Andes mountain range. |
Mt. Erebus in an active volcano. Located in Ross Island. Only continent called white continent because the ice cap in 4,000 metres deep. |
3. Great Barrier Reef and Artesian Basin.
Barrier Reef |
Artesian Basin |
1. It is located in the north east of Australia along the east coast of queensland in the Pacific Ocean. |
The Artesian Basin are region on the earth’s surface where water gushes out like a fountain. |
2. It is formed by the tiny coral polyps. |
Largest and deepest basin in the world |
3. It is about 2300 km long. |
Located in the west of the Great Dividing range. |
4. One of the natural wonders of the world |
Found in arid and Semi- arid parts of Queensland. |
VII. Give reasons.
1. Egypt is called the gift of the Nile.
- Egypt is called an gift of Nile.
- As it is the lifeline of the Egypt.
- Without Nile the Egypt would have bean a desert.
2. Deserts are found in the western margins of the continents.
- Most deserts are found in the Western margins in the sub tropics.
- Because the prevailing winds in the tropics are tropical eaterly winds.
- The tropical easterly winds become dry by the time they reach the western margins.
3. Antarctica is called the continent of scientists.
- Scientists of any country are free to conduct experiments and collect data from Antartica.
- So it is called continent of scientists.
VIII. Answer in a paragraph each.
1. Give an account on mineral wealth of Australia.
- Minerals are the largest export item of Australia.
- It contributes about 10 % of country’s GDP.
- Australia is the world’s leading producer of bauxite, limonite, the second largest producer of gold. lead, lithium, manganese ore and zinc.
- The third largset producer of iron ore and uranium and the fourth largest producer of black coal.
- The Coal belts of the country stretches from New castle to Sydney.
- Iron ores are found mainly in southern and Western Australia.
- Bauxite is mined around the gulf of Carpentaria.
- Uranium is mined in northern territory.
- Gold is mined in Western desert at kalgoorlie and Koolgarlie.
2. Describe the flora and fauna of Antarctica.
- No Major vegetation is found in Antartica as the temperature is freezing.
- Simple plants like algae, mosses, liverworts, lichens and microscopic fungi alone can survive.
- Few species like plankton algae and mosses are found in Antarctica’s fresh and saltwater lakes.
- Small red fish called krill are found in large shoals.
- The blue whale is the largest animal which feeds on plankton.
- The birds have webbed feet and flipper instead of wings.
3. Name the physical divisions of Africa and explain any one.
The physical divisions of Africa are.
- Sahara
- Sahel
- Savanna
- The great Rift Valley and the Great Lakes of Africa ‘
- East Africa Highlands
- Swahili Coast
- The Congo Basin or Zaire Basin
- Southern Africa.
Sahel:
- Sahel means border or margin. Sahel is a semi-arid tropical Savannah region lies between Sahara.
- Desert in the north and grass land into south.
- It Stretches east-west for a distance of 4000 km and covers an area of 30 million sq Km.
- It is largely a semi-arid belt of barren, sandy and rocky land.
- This region marks the physical and cultural transition between the more fertile tropical regions in the south and desert in the north.