Environment

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

• Carnivores
• Herbivores
• Decomposers
• Producers
  
  Answer: (a) Carnivores

An ecosystem includes

• All living organisms
• Non-living objects
• Both living organisms and non-living objects
• 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

• 5 k J
• 50 k J
• 500 k J
• 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

• Eutrophication
• Pollution
• Biomagnification
• Accumulation
  
  Answer: (c) Biomagnification

Depletion of ozone is mainly due to

• Chlorofluorocarbon compounds
• Carbon monoxide
• Methane
• Pesticides
  
  Answer: (a) Chlorofluorocarbon compounds

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

• Decomposers
• Producers
• Herbivores
• 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

• Heat energy
• Light energy
• Chemical energy
• 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

• Food web
• Ecological pyramid
• Ecosystem
• Food chain
  
  Answer: (b) Ecological pyramid

Flow of energy in an ecosystem is always

• Unidirectional
• Bidirectional
• Multi directional
• No specific direction
  
  Answer: (a) Unidirectional