CBSE Class 12 Environmental Issues — practice questions
42 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice CBSE Class 12 Environmental Issues in the app →Which of these is a terrestrial ecosystem?Which is a man-made ecosystem?The basic energy input to any ecosystem is:Green plants in an ecosystem are called:Animals that feed directly on plants are:Producers belong to which trophic level?Energy movement through trophic levels is:The rate of biomass production is called:GPP minus respiration losses equals:The rate at which consumers form new organic matter is:The annual net primary productivity of the biosphere is about:Raw material for decomposition is called:Which is NOT a step of decomposition?Plants capture what share of photosynthetically active radiation?Decomposition is slower when detritus is rich in:Which conditions favour decomposition?The mass of living material at a trophic level is the:The pyramid of biomass in the sea is generally:Which ecological pyramid can never be inverted?Which group is left out of ecological pyramids?A factory's smoke changes the air in an unwanted way. Anything causing such a change is a:A thermal power plant removes over 99 percent of dust from its exhaust using an:Cars with catalytic converters must use unleaded petrol because lead:Noise was added as an air pollutant when the Air Act of 1981 was amended in:By the end of 2002 all Delhi buses had switched from diesel to:The amount of biodegradable organic matter in sewage is estimated by measuring:Downstream of a sewage outlet, fish die because microbes consume the:Excess nutrients turn a pond green with free-floating algae. This is an:The water hyacinth, a lovely-flowered weed choking Indian waterways, is called the:DDT at 0.003 ppb in water reaches 25 ppm in fish-eating birds. This rise up the food chain is:High DDT in birds disturbs calcium metabolism and causes:The natural aging of a lake by nutrient enrichment is called:Open garbage dumps breed rats and flies. They were replaced by:A greenhouse warms up because its glass lets light in but:The two gases named as the main greenhouse gases are carbon dioxide and:Good ozone that shields us from UV lies in the:The refrigerant chemicals that destroy stratospheric ozone are:A single Cl atom keeps destroying ozone because it acts as a:The ozone hole appears each year above:The 1987 treaty to control ozone-depleting substances is the:The National Forest Policy of 1988 recommends what forest cover for the plains?In 1974 women of the Garhwal Himalayas hugged trees to stop contractors. This was the: