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Environment

Exemplar Problems MCQ I

Which one of the following is an artificial ecosystem?

1. Pond
2. Crop field
3. Lake
4. Forest
   
   Answer: (b) Crop field

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In a food chain, the third trophic level is always occupied by

1. Carnivores
2. Herbivores
3. Decomposers
4. Producers
   
   Answer: (a) Carnivores

In a food chain, the second trophic level is always occupied by

1. Carnivores
2. Herbivores
3. Decomposers
4. Producers
   
   Answer: (b) Herbivores

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An ecosystem includes

1. All living organisms
2. Non-living objects
3. Both living organisms and non-living objects
4. Sometimes living organisms and sometimes non-living objects
   
   Answer: (c) Both living organisms and non-living objects

In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, what will be the energy available at the producer level?
Grass ↠ Grasshopper ↠ Frog ↠ Snake ↠ Hawk

1. 5 k J
2. 50 k J
3. 500 k J
4. 5000 k J
   
   Answer: (d) 5000 kJ

Accumulation of non-biodegradable pesticides in the food chain in increasing amount at each higher trophic level is known as

1. Eutrophication
2. Pollution
3. Biomagnification
4. Accumulation
   
   Answer: (c) Biomagnification

Depletion of ozone is mainly due to

1. Chlorofluorocarbon compounds
2. Carbon monoxide
3. Methane
4. Pesticides
   
   Answer: (a) Chlorofluorocarbon compounds

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Organisms which synthesise carbohydrates from inorganic compounds using radiant energy are called

1. Decomposers
2. Producers
3. Herbivores
4. Carnivores
   
   Answer: (b) Producers

In an ecosystem, the 10% of energy available for transfer from one trophic level to the next is in the form of

1. Heat energy
2. Light energy
3. Chemical energy
4. Mechanical energy
   
   Answer: (c) Chemical energy

Organisms of a higher trophic level which feed on several types of organisms belonging to a lower trophic level constitute the

1. Food web
2. Ecological pyramid
3. Ecosystem
4. Food chain
   
   Answer: (b) Ecological pyramid

Flow of energy in an ecosystem is always

1. Unidirectional
2. Bidirectional
3. Multi directional
4. No specific direction
   
   Answer: (a) Unidirectional

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