80 RAS Prelims MCQs on natural vegetation and biomes ask about the forest types of the world, their layers, trees and soils. The Amazon rainforest, temperate rainforests, the boreal forest, the temperate deciduous forest and the Great Barrier Reef are tested, and each explanation links the biome to its climate and location.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 51–60 of 80 questions
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q51. Consider the following statements regarding the needle-shaped leaves of coniferous trees in the Boreal (Taiga) forest: I. They reduce the surface area, thereby minimizing water loss through transpiration. II. Their waxy coating protects them from freezing temperatures. III. The shape allows snow to easily slide off, preventing branch breakage. IV. They fall off every winter to conserve energy. V. They are dark in color to maximize the absorption of weak winter sunlight. Which of the above statement(s) is/are incorrect?
Explanation
Coniferous trees in the boreal forest have evolved needle-shaped leaves to survive harsh winters. Their small surface area and waxy coating reduce water loss and prevent freezing. The shape also prevents snow accumulation from breaking branches. Most boreal conifers are evergreen and do not shed their leaves in winter; this allows them to begin photosynthesis immediately when temperatures rise in spring.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q52. Which of the following statements accurately distinguishes Alpine Tundra from Arctic Tundra?
Explanation
While both biomes are treeless and cold, Arctic tundra and alpine tundra are distinguished by their location. Arctic tundra occurs at high latitudes near the poles and is often underlain by permafrost. Alpine tundra is found at high altitudes on mountains worldwide, regardless of latitude. In alpine regions, better drainage and the lack of continuous permafrost often result in different soil characteristics.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q53. The following question consists of two statements--Statement I and Statement II. Answer the question by selecting the appropriate option. Statement I: Phreatophytes are a specific type of desert plant adapted to arid environments. Statement II: They survive dry conditions by developing extremely long taproots that reach deep underground water tables.
Explanation
Phreatophytes are a specialized group of desert plants that have adapted to arid conditions by developing extremely long taproots. These roots extend deep into the earth to reach the underlying water table, providing a consistent moisture source. This strategy allows them to remain green and survive even when the surface soil is completely dry and other vegetation has withered away.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q54. Mangrove forests play a critical ecological role in coastal regions. Which of the following is not a recognized ecological benefit of mangroves?
Explanation
Mangroves provide essential ecological services, such as protecting coasts from erosion, trapping sediment, and serving as nurseries for marine life. They act as natural filters for pollutants before they reach the ocean. However, mangroves do not increase the salinity of coastal waters to support freshwater fish. Instead, they are highly adapted to survive and thrive in saline or brackish water environments.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q55. The Great Barrier Reef, the world’s largest coral reef system known for its immense biodiversity, is located in the waters off the coast of:
Explanation
The Great Barrier Reef is the largest and most famous coral reef system on Earth, spanning thousands of kilometers. It is located in the Coral Sea, off the northeastern coast of Australia. This massive structure is built by billions of tiny coral polyps and supports an incredible diversity of marine life, making it a globally significant site for marine conservation and biodiversity.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q56. Which of the following pairs of Biome and Soil fertility is correctly matched?
Explanation
Temperate grasslands possess some of the most fertile soils globally, often classified as Mollisols or Chernozems. These soils are deep and rich in organic matter due to the annual decomposition of extensive grass root systems. In contrast, tropical rainforest soils are typically nutrient-poor and leached, while tundra soils are often frozen, and desert soils are frequently thin and lack organic material.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q57. Which of the following statements regarding the boundaries of biomes is incorrect?
Explanation
Biome boundaries are rarely sharp or sudden. Instead, they usually consist of gradual transition zones known as ecotones. In these areas, the characteristics of adjacent biomes overlap, often leading to higher species diversity through the edge effect. This gradual shift reflects the slow changes in climate, such as temperature and precipitation, as one moves across different latitudes or altitudes.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q58. In the context of tropical rainforest vegetation, what is the correct definition of "Lianas"?
Explanation
Lianas are woody, climbing vines that are a prominent feature of tropical rainforests. They begin their life on the forest floor but quickly grow upward, using trees for physical support to reach the sunlight-rich canopy. Once established, they often loop between trees, providing pathways for arboreal animals. They are autotrophic and compete with trees for light, nutrients, and water.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q59. Many emergent and canopy trees in the tropical rainforest have prominent "buttress roots". What is their primary function?
Explanation
Buttress roots are large, wide roots that grow out from the base of many tall tropical rainforest trees. Their primary function is to provide structural stability and support for the massive trunks in the shallow, nutrient-poor soils of the rainforest. Because most nutrients are near the surface, these trees do not have deep taproots, making buttress roots essential for preventing toppling.
RAS PrelimsWorld Geography · Natural Vegetation and Biomes
Q60. The Indian subcontinent is largely characterized by tropical deciduous forests. Which of the following tree species is generally not found in these forests?
Explanation
India’s tropical deciduous forests are dominated by commercially important species like teak, sal, and neem, which are well-adapted to the seasonal monsoon climate. Mahogany, however, is a tree species characteristic of tropical evergreen rainforests. It requires consistent high humidity and rainfall throughout the year, conditions that are not typical of the deciduous forest regions found across the Indian subcontinent.
Answer key for these questions
Q
Correct answer
51
(b) IV only
52
(d) Alpine Tundra occurs at high altitudes, while Arctic Tundra occurs at high latitudes
53
(a) Both Statement I and Statement II are correct
54
(c) They increase the salinity of coastal waters, making them suitable for freshwater fish
55
(d) The northeastern coast of Australia
56
(a) Temperate Grassland : Highly fertile soil with a thick, dark humus layer
57
(c) Biome boundaries are sharply defined, with one biome ending abruptly where another begins
58
(a) Woody vines rooting in soil that climb trees to reach the canopy
59
(d) To provide structural support in shallow, nutrient-poor soils
60
(b) Mahogany
Key facts from Natural Vegetation and Biomes
The dense, broad-leaved evergreen forest of the Amazon Basin is called Selvas.
The layers of a tropical rainforest from the top are emergent layer, canopy, understory and forest floor; epiphytes grow on other plants for support without being parasites.
Podzolization is the soil process most dominant in the Boreal Forest (Taiga).
Boreal forests have extensive pure stands of a single species, which simplifies commercial lumbering.
Temperate deciduous forests are found in eastern United States, western Europe and eastern China.
The Coastal Redwood is a famous tree of the Pacific coast temperate rainforest; the Great Barrier Reef lies off the north-east coast of Australia.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Natural Vegetation and Biomes?
This page has 80 practice MCQs on Natural Vegetation and Biomes (World Geography). Each has the correct answer, and most have an explanation.
What are Selvas?
The local name for the dense, broad-leaved evergreen forest of the Amazon Basin. The high rainfall and heat all year round produce a tall forest with several layers, which makes it the richest rainforest on the planet.
What are epiphytes?
Plants that grow on other plants, mostly trees, for physical support, without being parasites. In tropical rainforests orchids and ferns are epiphytes, and they get light by growing high on tree trunks and branches.
Where is podzolization most common?
In the Boreal Forest, or Taiga, biome. The cold, wet climate and acidic needle litter wash minerals out of the upper soil, producing the grey, infertile podzol soils typical of coniferous forests.
