Environment & Ecology Previous Year Questions (PYQ) with Answers – Page 13

All three statements are correct. Methane hydrate, also called gas hydrate or "fire ice", is methane trapped inside a cage of frozen water molecules.

Microbeads are tiny plastic particles that wash into rivers and seas, where they persist and are eaten by marine life.

The blue-finned mahseer occurs in the Cauvery and the rusty-spotted cat in the Eastern Ghats, but the Irrawaddy dolphin does not live in the Chambal.

These protected areas lie at the southern tip of the Western Ghats, where the Agasthyamala Biosphere Reserve spreads across Kerala and Tamil Nadu.

Pyrolysis and plasma gasification are two thermal methods of turning solid waste into fuel gas, oil or power.

Both ideas are geoengineering proposals meant to cool the planet by changing how much heat enters or leaves the Earth.

Only the Asiatic lion survives in the wild in India alone, in the Gir landscape of Gujarat. The Asiatic lion once ranged from West Asia to central India, but today its only wild population lives in and around Gir National Park and the nearby districts of Saurashtra in Gujarat.

Set high in the Garhwal Himalaya of Uttarakhand, roughly between 3,200 and 6,600 metres, it lies wholly in the temperate alpine zone.

A caterpillar feeds directly on green leaves, so it is a herbivore, which is what a primary consumer is. In a food chain energy flows from producers to consumers.

An ecosystem is a working unit in which a community of living organisms interacts with the non-living surroundings in a given area, so it must contain both halves.

Sulphur dioxide is an air pollutant but it is not counted among the greenhouse gases. A greenhouse gas is one that lets sunlight through but absorbs the long wave infrared radiation the earth sends back, so it warms the lower atmosphere.

Successive assessments by the Forest Survey of India have placed Madhya Pradesh first among the States in the absolute area under forest cover, a position it owes to its very large size and to the extensive teak and sal forests of the Satpura, Vindhya and Baghelkhand tracts.

Most renewable sources depend on the weather, so the power they give is intermittent rather than steady. Solar panels make nothing at night and little under thick cloud, wind turbines stop when the wind drops, and hydropower falls away in a weak monsoon.

The decibel, written dB, is the unit in which the intensity level of sound is expressed, and it is named after Alexander Graham Bell.

Carbon monoxide is a dangerous air pollutant, but it is not counted among the major greenhouse gases, because it absorbs very little of the infrared heat leaving the earth.

A shelter belt is a row or a block of trees and shrubs planted across the direction of the prevailing wind.

The savanna is a tropical grassland with tall coarse grass and scattered flat topped trees, and its wet season produces an enormous crop of grass.

Fly ash is the fine, powdery residue that rises with the flue gases when pulverised coal is burnt to raise steam in a coal-fired power station.

Anthracite is the oldest and hardest grade of coal, with the highest proportion of carbon, so it gives the most heat for its weight and burns with a clean, almost smokeless flame.

This describes geothermal energy. Molten rock pushed up from deep inside the Earth collects as hot spots at shallower depths, and groundwater trapped near them is heated until it becomes steam under high pressure.