[{"id":178772,"question":"The total energy from the sun is happened by the producers in an ecosystem is about?","choices":[{"text":"20 %","value":"A"},{"text":"10 %","value":"B"},{"text":"5 %","value":"C"},{"text":"1 %","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":178771,"question":"The best way to increase food production from ecosystem view point is:","choices":[{"text":"To increase cultivable land by clearing forest","value":"A"},{"text":"Use of excessive fertilizers","value":"B"},{"text":"Use of high quality pesticides","value":"C"},{"text":"Use of genetically improved varieties of seeds","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":178770,"question":"Which of the following is NOT recycled in ecosystem?","choices":[{"text":"Carbon","value":"A"},{"text":"Sulphur","value":"B"},{"text":"Energy","value":"C"},{"text":"Water","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":178768,"question":"What would be expected to happen if all the nitrogen-fixing organisms ceased to exist?","choices":[{"text":"There would be no significant change in number of animals","value":"A"},{"text":"The total number of biomass would be reduced","value":"B"},{"text":"All organisms would die out","value":"C"},{"text":"The nitrogen level of the atmosphere would be increase","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":178767,"question":"Which statement defines the net primary production in an ecosystem over a given time period?","choices":[{"text":"The total amount of organic matter in the plants in excess of that used in respiration","value":"A"},{"text":"The total amount of organic matter used in respiration by all the organisms present","value":"B"},{"text":"The total amount of photosynthesis product from all plants","value":"C"},{"text":"The total amount of organic matter in all organisms present","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":178766,"question":"The amount of energy left plants have met their respiratory needs is net eprimary production , which shows up as plant:","choices":[{"text":"Respiration rate","value":"A"},{"text":"Photosynthesis","value":"B"},{"text":"Biomass","value":"C"},{"text":"Food reserve","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":178765,"question":"In succesion lithoseres takes place on:","choices":[{"text":"Sand","value":"A"},{"text":"Water","value":"B"},{"text":"Forest floor","value":"C"},{"text":"Bare rocks","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":178764,"question":"A change in the community structure of an ecosystem over a period of time is:","choices":[{"text":"Ecological niche","value":"A"},{"text":"Ecological mutation","value":"B"},{"text":"Succession","value":"C"},{"text":"Genetic Drift","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":2764,"question":"At the time of independence in 1947 the population of pakistan was","choices":[{"text":"10 m","value":"A"},{"text":"20 m","value":"B"},{"text":"25.7 m","value":"C"},{"text":"32.5 m","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":2763,"question":"The decline in thickness of the ozone layer is caused by increasing level of","choices":[{"text":"Chlorofluorocarbon","value":"A"},{"text":"Nitrogen","value":"B"},{"text":"Chlorine","value":"C"},{"text":"Carbon dioxide","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":2761,"question":"Rain that falls on high areas such as mountains possesses large amount of garvitational","choices":[{"text":"Heat energy","value":"A"},{"text":"Kinetic energy","value":"B"},{"text":"Electrical energy","value":"C"},{"text":"Potential energy","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":2759,"question":"Oxone molecule is made up by binding of three atoms of","choices":[{"text":"Nitrogen","value":"A"},{"text":"Oxygen","value":"B"},{"text":"Hydrogen","value":"C"},{"text":"Carbon","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":2758,"question":"Only 30% of the earth is dry land the remainder being covered with","choices":[{"text":"Water","value":"A"},{"text":"Air","value":"B"},{"text":"Trees","value":"C"},{"text":"Grass","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":2757,"question":"Modern man is called","choices":[{"text":"Homo erectus","value":"A"},{"text":"Homo habilis","value":"B"},{"text":"Homo sapiens","value":"C"},{"text":"Homo neanderthalensis","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":2756,"question":"In oceans especially in tropical regions temperature of surface water is about","choices":[{"text":"10<sup>o</sup>C","value":"A"},{"text":"15<sup>o</sup>C","value":"B"},{"text":"25<sup>o</sup>C","value":"C"},{"text":"35<sup>o</sup>C","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":2754,"question":"A natural process in which surface soil is removed by the action of water or wind is","choices":[{"text":"Corrosion","value":"A"},{"text":"Attrition","value":"B"},{"text":"Erosion","value":"C"},{"text":"Weathering","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":2749,"question":"Each nuclear power station only can last for about","choices":[{"text":"10 years","value":"A"},{"text":"20 years","value":"B"},{"text":"30 years","value":"C"},{"text":"40 years","value":"D"},{"value":"E"}],"correctAnswer":3}]