Previous Year UPSC Questions

Explanation

The drastic decline in the vulture population in India is primarily attributed to the use of a veterinary drug called diclofenac. This drug was commonly administered to cattle to treat inflammation and pain. However, when vultures fed on the car-casses of cattle that had been treated with diclofenac, they suffered from kidney failure and fatal toxicity, leading to a sharp decline in their population.

Explanation

When a pollen grain moves from the anther (male part) of a flower to the stigma (female part), pollination happens and it is the first step in a process that produces seeds, fruits, and the next generation of plants. Vectors that move pollen within the flower and from flower to flower are called pollinators.

Option (d) is correct:

Pollination is the transfer of pollen grains from the stamens (the flower parts that produce them) to the ovule-bearing organs or to the ovules (seed precursors) themselves. There are two categories of pollinators, i.e. invertebrate pollinators which includes bees, moths, flies, wasps, beetles and butterflies and verte-brate pollinators which has monkeys, rodents, lemurs, tree squirrels, bats and birds. The fruit bats (also known as megabats) and nectar-feeding bats are particularly involved in pollination. Bats are vital for the pollination of various species, including certain species of cacti, bananas, and agave plants, which rely on them for reproduction. Bees are some of the most efficient and well-known pollinators. Bees are responsible for pollinating a significant portion of the world’s food crops. Certain species of birds, particularly hummingbirds and some species of sunbirds, are also important pollinators. They feed on nectar and, in the process, move pollen from one flower to another. This form of pollination is common in plants with red or orange flowers that attract birds and require birds with long bills or beaks for feeding.

Explanation

Seabuckthorn (soil binding, rich in vitamins) is a shrub which produces an orange-yellow coloured edible berry. It can be found in India above treeline in the Himalayan region, usually in arid places like the cold deserts of Ladakh and Spiti. Seabuckthorn grows naturally in Lahaul, Spiti, and some regions of Kinnaur in Himachal Pradesh. Statements 1 and 3 are correct: Seabuckthorn is a soil-bind-ing plant which prevents soil-erosion, it also has commercial value, as it is used in making juices, jams, nutritional capsules etc.

Statement 2 is incorrect: While sea buckthorn has various uses, including medicinal and nutritional, it is not primarily known for being a biodiesel source. While some studies have explored its potential as a biofuel, it is not widely regarded as a primary source of biodiesel.

Statement 4 is incorrect: Sea buckthorn does not have significant commercial value for its timber. The plant is primarily valued for its fruits, oils, and medicinal properties, not for timber production.

Explanation

The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological species. Great Indian Bustard, Musk Deer, Red Panda and Asiatic Wild Ass (Currently Vulnerable, but as the question is from 2012, we will consider it as Endangered) all are Endangered Species. Important species and their Conservation status are:

Species Particulars Great Indian Bustard State bird of Rajasthan Flagship grassland species, representing the health of the grassland ecology. States: Rajasthan and Gujarat. Small populations occur in Maharashtra, Karnataka and Andhra Pradesh. Conservation Status: Critically Endangered Musk Deer Habitat: J&K, Uttarakhand. Himachal Pradesh, Sikkim and Arunachal Pradesh. Conservation Status: Endangered Red Panda Red panda is endemic to the temperate forests of the Himalayas. Habitat: Sikkim and Assam, northern Arunachal Pradesh. Threats: habitat loss and fragmentation, poaching, and inbreeding depression. Conservation Status: Threatened Species Asiatic Wild Ass Scientific Name: Equus hemionus Also called: Asiatic Wild Ass, Asian Wild Ass, Indian onager or, Ghudkhur and Khur (Gujarati language) Habitat: Western India, southern Pakistan (i.e. provinces of Sindh and Baluchistan), Afghanistan, and south-eastern Iran. Conservation Status:

IUCN: currently listed as Near Threatened (Earlier it was listed under Endangered Category)

Explanation

The Chiru, or Tibetan Antelope, is adapted to the cold, high-altitude regions of the Tibetan Plateau, steppes, and semi-desert areas. These regions are characterized by cold temperatures and sparse vegetation. Chiru is well-suited to survive in these challenging environments. It is primarily poached for its fine wool, known as Shahtoosh rather than for musk. Oryx is a type of antelope that is adapted to hot, arid, and desert regions, such as the Thar Desert in western India and regions in Africa. These antelopes are well-suited to extreme heat and dryness due to their ability to survive with very little water, and they often thrive in desert environments. It is poached for its horns and meat.

Explanation

Option 1 is correct: Black-necked crane is a state bird of Ladakh. It is found in northeastern Ladakh and some parts of Himalayan foothills in India. It is endemic to the Tibetan Plateau and migrates to India during the winter months. It is listed as vulnerable and is considered an important species for conservation.

Option 2 is incorrect: The Cheetah was historically found in India but was declared extinct in India in the 1950s due to hunting and habitat loss. However, the species is now being re-introduced in India, especially in Kuno National Park, Madhya Pradesh.

Option 3 is correct: In India, most of these species are found in the eastern Himalayas and the north-east, at the confluence of two biogeographically significant regions, the Himalayan and the Indo-Malayan regions. These arboreal mammals are adapted to glide between trees in search of food.

Option 4 is correct: The Snow Leopard is found in high-alti-tude regions of Himachal Pradesh, Ladakh, and parts of Uttarakhand and Sikkim. It is classified as vulnerable and is an apex predator in cold mountain ecosystems.

Explanation

Option 1 is correct: Rising temperatures are affecting biodiversity. Global warming induced climate change is causing changing rainfall patterns, extreme weather events, and ocean acidification. These are putting pressure on species already threatened by other human activities.

Option 2 is correct: Mammals and birds that require large territories as well as animals with migratory habitat are adversely affected by fragmentation of Habitat. This results in population decline.

Option 3 is correct: Invasive alien species are animals, plants, fungi and microorganisms entered and established in the environment from outside of their natural habitat. They reproduce rapidly, outcompete native species for food, water and space, and are one of the main causes of global biodiversity loss.

Option 4 is incorrect: Promotion of vegetarianism is not a cause for the loss or threat of biodiversity.

Explanation

The Himalayas are the youngest fold mountains in the world. They exhibit dynamic geological features shaped by tectonic activity. These features provide evidence of their youthful and evolving nature, making them a fascinating subject for geologists and travelers alike. All the given features--deep gorges, U-turn river courses, parallel mountain ranges, and steep gradients causing landslides--are evidence of the Himalayas being young fold mountains. These characteristics result from ongoing tectonic uplift, erosion, and the mountains’ relatively recent formation (around 50 million years ago).

Explanation

Monsoon refers to a seasonal change in wind patterns that results in a shift in precipitation patterns over a region. Monsoons occur primarily in tropical and subtropical regions and are characterized by a wet season and a dry season.

Statement 1 is correct: The monsoon duration decreases from southern India (June-September) to northern India (July-August) due to the gradual weakening of monsoon winds as they move inland. Due to its proximity to the sea, India’s southern region has earlier and longer rainy seasons than its northern region.

Statement 2 is correct: The northern plains experience a rainfall gradient, with higher rainfall in the east (Assam, West Bengal) and decreasing towards the west (Punjab, Rajasthan) due to the weakening of monsoon winds. During the southwest monsoon, Kolkata receives 119 cm, Patna 105 cm, Allahabad 76 cm, and Delhi 56 cm.

Explanation

Arunachal Pradesh has the following mentioned characteristics:

Northern Rajasthan lies approximately between 26°N to 27°N latitude. Arunachal Pradesh (27°N-29°N) closely aligns with this latitude range. Assam (24°N-28°N), Himachal Pradesh (30°N-33°N), and Uttarakhand (29°N-31°N) are either too far north or south. As per the India State of Forest Report (ISFR) 2021, Arunachal Pradesh has 82.4% forest cover. While Assam has 35.83%, Himachal Pradesh 27.72%, and Uttarakhand 45.44%. Arunachal Pradesh has over 12% of its forest area designated as Protected Areas, including Namdapha National Park, Pakke Wildlife Sanctuary, and Mouling National Park.