Deserts & Grasslands — Set 3

Correct Answer: A. Arctic regions

• **Tundra** = treeless cold ecosystem found in the Arctic and on mountaintops, characterized by permafrost, with vegetation of mosses, lichens, and small shrubs. • **Permafrost** — the subsoil in tundra is permanently frozen (permafrost); only the top layer thaws briefly in summer; tundra covers about 10% of Earth's land surface. • 💡 Wrong-option analysis: Tropical regions: have tropical rainforests (Selvas, Congo) and Savanna grasslands, not tundra; Equatorial regions: have dense tropical rainforests due to year-round high rainfall; Desert regions: have hot or cold arid ecosystems, distinct from tundra.

Correct Answer: D. Kyzylkum Desert

• **Kyzylkum Desert** = the 16th largest desert in the world, in Central Asia between the Amu Darya and Syr Darya rivers, shared by Uzbekistan and Kazakhstan. • **'Red Sand'** — Kyzylkum means 'Red Sand' in Turkic languages; the desert covers about 298,000 sq km and is home to various unique reptiles and rare animals. • 💡 Wrong-option analysis: Arabian Desert: in the Arabian Peninsula, Asia, bounded by Red Sea and Persian Gulf; Sahara Desert: in North Africa, the world's largest hot desert; Sonoran Desert: in southwestern USA and northwestern Mexico.

Correct Answer: A. Brazil

• **Campos** = tropical grasslands found in southern Brazil and parts of Paraguay, similar to Savanna but at higher altitudes, widely used for agriculture and grazing. • **Cerrado** — the Campos are part of the broader Cerrado biome of Brazil, the world's most biodiverse tropical savanna, covering about 2 million sq km of central Brazil. • 💡 Wrong-option analysis: Russia: has Steppes (temperate grasslands) in its southern regions; India: has tropical dry forests and semi-arid regions, not Campos; South Africa: has Veld (temperate grasslands) not Campos.

Correct Answer: A. Mojave Desert

• **Mojave Desert** = contains Death Valley in eastern California, the lowest (86 m below sea level) and hottest point on the North American continent. • **56.7°C** — Death Valley holds the world record for highest reliably recorded air temperature at 56.7°C (1913); it is 282 feet (86 m) below sea level. • 💡 Wrong-option analysis: Gibson Desert: in Western Australia, not known for Death Valley; Atacama Desert: in northern Chile, the driest desert, has no Death Valley; Thar Desert: between India and Pakistan, no such record-breaking temperature location.

Correct Answer: B. Australia

• **Great Sandy Desert** = arid region in northwest Western Australia, the second largest desert in Australia (after Great Victoria Desert), known for linear sand dunes. • **2nd largest in Australia** — the Great Sandy Desert covers about 284,000 sq km; the largest Australian desert is the Great Victoria Desert; others include Simpson and Gibson. • 💡 Wrong-option analysis: China: has the Gobi Desert and Taklamakan Desert; Saudi Arabia: has the Rub' al Khali (Empty Quarter) within the Arabian Desert; USA: has the Great Basin, Mojave, Sonoran, and Chihuahuan Deserts.

Correct Answer: A. Thar Desert

• **Thar Desert** = also called the Great Indian Desert, spans the India-Pakistan border, with most lying in Rajasthan (India); the world's most densely populated desert. • **Most densely populated desert** — unlike other deserts, the Thar supports a relatively large human population (~83 persons per sq km) due to the monsoon; it covers about 200,000 sq km. • 💡 Wrong-option analysis: Kalahari Desert: in southern Africa (primarily Botswana), not shared by India-Pakistan; Gobi Desert: in China and Mongolia, not South Asia; Arabian Desert: on the Arabian Peninsula in western Asia, not India-Pakistan.

Correct Answer: D. Boreal forest

• **Taiga** = also known as Boreal Forest, the world's largest land biome consisting primarily of coniferous forests in high northern latitudes of North America and Eurasia. • **Largest land biome** — the Taiga covers approximately 17 million sq km, representing about 29% of Earth's total forest area; characterized by long cold winters and short cool summers. • 💡 Wrong-option analysis: Tropical forest: found in equatorial regions (Amazon, Congo, SE Asia), different from boreal forest; Coastal desert: like the Namib or Atacama, found along coastlines in arid subtropical zones; Temperate grassland: Prairies, Pampas, Steppes — open grasslands with few trees.

Correct Answer: C. South America

• **Patagonian Desert** = largest desert in South America and 8th largest in the world, located in southern Argentina, a cold winter desert east of the Andes. • **8th largest globally** — the Patagonian Desert covers about 673,000 sq km; temperatures rarely exceed 12°C; the Andes create the rain shadow that makes it arid. • 💡 Wrong-option analysis: Europe: has Steppes and Puszta grasslands, no major deserts comparable to Patagonian; Africa: has the Sahara, Namib, and Kalahari deserts; Australia: has the Great Sandy, Gibson, Simpson, and Great Victoria Deserts.

Correct Answer: A. Mounds of sand formed by wind

• **Dunes** = landforms composed of wind-blown sand in the form of mounds or ridges, a common feature in most deserts and coastal regions. • **Wind-shaped forms** — dune shape (barchan, star, linear) and size are determined by wind speed, direction, and sand supply; the tallest dunes (up to 250 m) are found in the Rub' al Khali (Arabian Desert). • 💡 Wrong-option analysis: Underground water sources: these are called aquifers; they feed oases in deserts; Temporary seasonal lakes: these are called playas or 'wadis' (dry riverbeds) when they fill temporarily; Hard rocky plateaus: these are called 'Reg' (gravel plains) or 'Hammada' (rocky desert surfaces) in Saharan terminology.

Correct Answer: B. Arabian Desert

• **Rub' al Khali (Empty Quarter)** = the world's largest continuous sand desert, covering the southern third of the Arabian Peninsula, part of the Arabian Desert. • **650,000 sq km** — the Rub' al Khali covers about 650,000 sq km with dunes up to 250 m high; it spans Saudi Arabia, UAE, Oman, and Yemen; uninhabited due to extreme conditions. • 💡 Wrong-option analysis: Gobi Desert: in China and Mongolia, a cold desert with rock and gravel, not a sand sea; Sahara Desert: the largest hot desert in North Africa, a separate desert system entirely; Kalahari Desert: in southern Africa (Botswana), a semi-arid savanna, not a sand sea.