CBSE
Multiple Choice QuestionsSecondary productivity is rate of formation of new organic matter by
producer
parasite
consumer
decomposer
Acid rain is caused by
NO2
SO2 and NO2
SO3
CO2
Which one of the following processes during decomposition is correctly described?
Fragmentation - Carried out by organisms such as earthworm
Humification - Leads to the accumulation of a dark coloured substance humus, which undergoes microbial action at a very fast rate
Catabolism - Last step in the decomposition under fully anaerobic condition
Leaching - Water soluble inorganic nutrients rise to the top layers of soil
Identify the correct type of food chain
Dead animal > Blow fly maggots > Common frog > Snake
Grazing food chain
Detrital food chain
Decomposer food chain
Predator food chain
Trophic levels in ecosystem is formed by
only bacteria
only plants
only herbivores
organisms linked in food chain
Pyramid of energy in ecosystems is
always upright
always inverted
mostly upright
mostly inverted
Main cause of eutrophication is
fluctuation of temperature
unusual growth of aquatic vegetations
enrichment of nutrients
abundance of microorganisms
Which of the following is an example of man-made ecosystem
Herbarium
Aquarium
Tissue culture
Forest
The removal of 'Keystone' species will affect the
producers
consumers
ecosystem
decomposers
When the two ecosystems overlap each other, the area is called
habitat
niche
ecotone
ecotype
