STANDARD TENPART I & IICHAPTER : 12Our Environment /15 0 votes, 0 avg 289 SCIENCE AND TECHNOLOGY – Chapter 12 Our Environment 1 / 15 Global warming is a phenomenon related to: Evaporation Ecological balance Greenhouse effect Desertification 2 / 15 Which of the following substances will not be converted to compost when added in a composting pit? Waste paper Fruit and vegetable peels Human and animal excreta Plastic bags 3 / 15 What will happen if deer is missing in the food chain given below?Grass → Deer → Tiger The population of tiger increases The population of grass decreases Tiger will start eating grass The population of tiger decreases and the population of grass increases 4 / 15 The substance which is chiefly responsible for the depletion of ozone layer is: CFCs CH4 DDT O3 5 / 15 Which of the following radiations is responsible for the conversion of atmospheric oxygen to ozone? Gamma radiations Cosmic radiations Infrared radiations Ultraviolet radiations 6 / 15 If 100 J energy is available at the producer level in a food chain then the energy available to the secondary consumer will be: 10 J 0.1 J 1 J 0.01 J 7 / 15 Which among the following is a correct full form for DDT? Dichlorodiphenyltrichloroethane Dichlorodiphenyltetrachloroethane Dichlorodecaphenyltrichloroethane Dichlorodiethyltrichloroethane 8 / 15 Which of the following may be a conclusion of the excessive exposure of humans to sun’s ultraviolet rays?i. Peptic ulcersii. Eye disease like cataractiii. Damage to lungsiv. Skin cancer (i) and (iv) (ii), (iii) and (iv) (ii) and (iv) Only (iv) 9 / 15 We should reduce the use of the plastic bags, bottles etc. because: They are not durable They are non-biodegradable They are made of toxic materials They react with the atmospheric gases 10 / 15 Every food chain in the ecosystem begins with………. which are the original source of food. Saprophytes Parasites Producers Herbivores 11 / 15 Which among the following statements is incorrect in view of the plants? They convert the solar energy into mechanical energy They prepare their food from organic compounds They are also called producers They are the initial source of energy in a food chain 12 / 15 Among the following choose the correct option which contains only biodegradable items?i. Wood, paper, PVCii. Paper, seeds, detergent,iii. Paper, animal excreta, woodiv. Wool, leaves, paper (i), (ii) and (iii) (i) and (iii) (ii), (iii) and (iv) (iii) and (iv) 13 / 15 In a food chain the second trophic level is occupied by: Carnivores Autotrophs Herbivores Producers 14 / 15 Green plants utilize ……… percent of sun’s energy to prepare their food by the process of photosynthesis? 1 percent 10 percent 20 percent 99 percent 15 / 15 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: Biological magnification Biological accumulation Chemical magnification Chemical accumulation Your score is 0% Restart quiz