1) Every food chain in the ecosystem begins with..........which are the original source of food. a) Saprophytes b) Parasites c) Producers d) Herbivores 2) We should reduce the use of the plastic bags, bottles etc. because a) They are not durable b) They are non biodegradable c) They are made of toxic materials d) They react with the atmospheric gases 3) Among the following choose the correct option which contains only biodegradable items? a) Wood, paper, PVC b) Paper, seeds, detergent c) Wool, leaves, paper d) Paper, animal excrete, plastic 4) Which among the following statements is incorrect in view of the plants? a) They prepare their food from organic compounds b) They are also called producers. c) They are the initial source of energy in a food chain. d) They convert solar energy into mechanical energy. 5) In a food chain the second tropical level is occupied by a) Carnivores b) Autotrophs c) Herbivores d) Producers 6) Green plants utilize.........percent of sun's energy to prepare their food by the process of photosynthesis? a) 10 percent b) 1 percent c) 20 percent d) 99 percent e) 90 percent 7) The process of accumulation of harmful chemical substances like pesticides, in the body of living organisms at each trophic level of a food chain is known as a) Biological accumulation b) Chemical magnification c) Biological magnification d) Chemical accumulation 8) Which of the following may be a conclusion of the excessive exposures of humans to sun's ultraviolet rays? a) Eye disease like cataract b) Skin cancer c) Damage to immune system d) All of the above 9) If 100J energy is available at the producer level in a food chain then energy available to the secondary consumer will be: a) 10J b) 0.1J c) 1J d) 100J e) 1000J 10) Which of the following radiations is responsible for the conversion of atmospheric oxygen to ozone? a) Gamma radiations b) Cosmic radiations c) Ultraviolet radiations d) None of the above 11) The substance which is chiefly responsible for the depletion of ozone layer is: a) CFCs b) CH4 c) DDT d) O3 12) What will happen if deer is missing in the food chain as given: Grass is eaten by deer and deer is eaten by tiger a) The population of tiger increases b) The population of grass decreases c) Tiger will start eating grass d) The population of tiger decreases and the population of grass increases 13) Which of the following substances will not be converted to compost when added in a composting pit? a) Waste paper b) Fruit and vegetable peels c) Human and animal excreta d) Plastic bags 14) The flow of energy in ecosystem is: a) Unidirectional b) Bidirectional c) Multidirectional d) No specific direction 15) The functional unit of environment is : a) Nitrogen b) Ecosystem c) Carbon d) Oxygen

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