Daily Quiz #19 UPSC Prelims Marathon – November 22, 2019

Explanation: The course of a river may be divided in 3 parts:
•Upper or Mountain Course (stage of youth): This begins at the source of river. The river is very swift here as it descends the steep slopes, forming deep, narrow and V-shaped valley. Other features of upper course are: Gorges, Rapids & waterfalls, River capture
•Middle or Valley Course (stage of maturity): Here, active erosion of banks widens the V-shaped valley. The volume of water increases with confluence of many tributaries and this increases river’s load. Development of meanders is a common feature here. Water flowing under gravity rarely flows straight for long distance. A winding course develops and irregularities of the ground force the river to swing in loops, forming meanders. Other features of middle course are: Interlocking spurs, River cliffs.
•Lower or Plain Course (stage of old age): Here, the river moving downstram across a broad, level plain is heavy with debris brought down from upper course. The river deposits its sediments, build up its bed and forms extensive flood plains.
Main features are formation of Ox-bow lake, Delta and Flood plain.
In lower course of river, meander becomes more pronounced. The outside bend or concave bank is so rapidly eroded that the river becomes almost a complete circle. There will be a time when the river cuts through the narrow neck of the loop, abandoning an ox-bow lake (meaning dead lake). The river then flows straight.
Delta is formed when a river reaches the sea. The fine materials which have not been dropped by the river are deposited at its mouth, which forms a fan-shaped alluvial area called a Delta.

Explanation: Option A is not correct. Andaman and Nicobar Islands are separated by Ten Degree Channel.
Option B is not correct. Kavaratti and Minicoy Islands are separated by Nine Degree Channel.
Option C is not correct. . Little Andaman and Car Nicobar Islands are separated by Ten Degree Channel.
Option D is correct. Minicoy and Maldives Island are separated by Eight Degree channel.

Explanation: Savanna type of climate:
Days are hot, and during the hot season, noon temperature goes beyond 100oF. When night falls the clear sky which promotes intense heating during the day also causes rapid radiation in the night. Temperatures drop to well below 50oF, and night frosts are common at this time of the year. This extreme Diurnal range of temperature is a characteristic feature of the Sudan type of climate.
The Savanna landscape is typified by tall grass and short trees. In true Savanna lands, the grass is tall and coarse, growing to 6-12 feet high. The Elephant Grass may attain a height of even 15 feet. The grass tends to grow in compact tufts and has long roots, which reach down in search of water.

Explanation: Turkey lies between Black sea and Mediterranean sea.

Explanation: The Tropical Grasslands have Savanna or Sudan type of climate. The belt includes West African Sudan, East Africa, and South Africa north of Tropic of Capricorn.
Pair 1 and Pair 2 are incorrectly matched. In South America, there are 2 distinct regions of Savanna: North and South of Equator. They are named as Llanos in Orinoco basin spread over Venezuela and Columbia, and Campos in Brazil.
Pair 3 is correctly matched. The Australian Savanna is located south of the monsoon strip running from west to east north of tropic of Capricorn.