The consumers utilize materials and energy stored by the producers.Decomposers obtain their food molecules from the organic materials of dead producers and consumers.A mutually beneficial association necessary for survival of both partners is (a) mutualism/symbiosis(b) commensalism(c) amensalism(d) both A and B. (a): Mutualism is an association between individuals of two species, both of which are benefitted but cannot live separately under natural conditions e.g.
Commensalism is the relationship between individuals of two species of which one is benefitted and the other is almost unaffected i.e.; neither benefitted nor harmed.6. (a) primary consumers are least dependent upon producers(b) primary consumers out-number producers(c) producers are more than primary consumers(d) secondary consumers are the largest and most powerful. (c): An ecosystem may be defined as a structural and functional unit of the biosphere comprising living organisms and their non-living environment that interact by means of food chains and chemical cycles resulting in energy flow, biotic diversity and material cycling to form a stable, self supporting system.
The organisms in an ecosystem are classified into 3 main categories-producers, consumers and decomposers.
Ecology is the study of the interactions and reciprocal influence of living organisms within a specific environment.
It's usually taught in the context of biology, though some high schools also offer courses in Environmental Science which includes topics in ecology.
These chlorofluorocarbons deplete the ozone layer in the higher atmosphere.
These CFC’s have produced a hole in the ozone layer.12.
Green house effect is warming due to (a) infra-red rays reaching earth(b) moisture layer in atmosphere(c) increase in temperature due to increase in carbon dioxide concentration of atmosphere(d) ozone layer of atmosphere. (c): The mean global temperature rise by 2° – 6°c and the concentration of carbon dioxide increases in the troposphere upto 600 ppm.
Hence, the surface of the earth becomes warm which causes global warming.
The regulation of water resources to prevent flood will help not only in soil conservation but also supply an adequate water supply in the period of drought.10.
The relation between algae and fungi in lichen is (a) symbiosis(b) parasitism(c) commenalism(d) protocooperation. (a): Algae and fungi in a lichen show symbiotic relationship.