Q1. State one problem caused by non-biodegradable wastes.
Q2. Which of the following materials are non-biodegradable in each of the following category?
(i) Paper, leather, nylon, eggshell, glass
(ii) Tea leaves, glass, glucose, cotton cloth, silver foil
(iii) Glass, glucose, leather, silver foil, nylon cloth
Q3. State one difference between autotrophs and heterotrophs.
Q4. Draw a food chain most likely to be a part of a forest ecosystem.
Q5. Rearrange the following according to their ascending trophic levels in a food chain. Hawk, grass, snake, frog, grasshopper.
Q6. If a harmful chemical enters a food chain comprising fishes, phytoplankton and birds, which of the organisms is likely to have minimum concentration of the harmful chemical in its body?
Q7. Rearrange the following according to their trophic levels in a food, chain.
Fish, zooplankton, sea, phytoplankton
Q8. Which one of the following is always at the third trophic level in a food chain?
Carnivores, herbivores, producers, decomposers.
Q9. In a food chain .comprising lion, grass and deer, which will
(i) transfer the maximum amount of energy.
(ii) receive a minimum amount of energy.
Q10. In the following food chain, 20 J of energy was available to the hawks. How much would have been present in the plants? –
Plants → rats → snakes → hawks
Q11. If a harmful chemical enters in food chain comprising snakes, peacock, mice and plants, which of these organisms is likely to have the maximum concentration of this chemical in its body?
Q12. The level of energy reaching from one to next higher trophic level decreases. Suggest a reason for this occurrence.
Q13. If the ozone layer disappears completely, what will be the consequences?
Q14. Name the group of chemical compounds which adversely affects the ozone layer?
Q15. To keep the environment clean, garbage disposal programme is an essential prerequisite. What methods constitute the garbage disposal programme?
Q16. List two methods of safe disposal of the non-biodegradable waste.
Q17. List two items which can be easily recycled, but we generally throw them in the dustbins?
Q18. A lake has been polluted by sewage. On comparison with the sample of unpolluted water, the water in the lake is found to have increased contents of some components. Identify these components.
Q19. Why should biodegradable and non-biodegradable wastes be discarded in two separate dustbins?
Q20. Write one negative effect of the affluent lifestyle of few persons of a society on the environment.
Q21. List two man-made ecosystems.
Q22. Name the two abiotic components of ecosystem.
Q23. The first trophic level in a food chain is always a green plant. Why?
Q24. Pesticides added to a field is seen in increased amount in the crop and in the birds that feed on them. What is this phenomenon called?
Q25. Why are some substance non-biodegradable?
Q26. Mention one negative effect of our affluent lifestyle on the environment.
Q27. State a way to prevent the accumulation of harmful chemicals in our bodies.
Q28. What is the ultimate source of energy in an ecosystem?
Q29. What happens when high energy ultraviolet radiations act on the oxygen at a higher level of atmosphere?
Q30. Are plants actually producers of energy?
Q31. How is being a vegetarian advantageous in terms of energy?
Q32. Does change in lifestyle add waste to the environment?
Q33. Give the difference between paper and glass as a waste product.
Direction (Q. Nos. 34 – 38) In each of the following questions, a statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion ·
(b) If both Assertion and Reason are true, but Reason is not the correct explanation of Assertion
(c) If Assertion is true, but Reason is false
(d) If Assertion is false, but Reason is true
(e) If Assertion and Reason both are false
Q34. Assertion: Food chains generally consists of more than four trophic levels.
Reason: There is loss of energy at each trophic level and very little usable energy remains after four trophic levels.
Q35. Assertion: Certain pesticides and other chemicals used to protect our crops from diseases and pests are non-bio degradable.
Reason: They do not get accumulated at various trophic levels.
Q36. Assertion: Ozone Layer protects life on earth by blocking out Infrared rays of the Sun.
Reason: Infra-red rays cause cancer in human beings.
Q37. Assertion: Producers are the largest in number in any food chain.
Reason: These large number of producers convert the sunlight into energy.
Q38. Assertion: An ecosystem consists of 3 to 4 tropic levels.
Reason: Removal of Primary consumers will not affect the ecosystem adversely.
Q39. Which trophic level is occupied by plants in a food chain?
Q40. Which of the following in an example of a human-made ecosystem?
Q41. What is the average value for the amount of organic matter that is present at each level of trophic chain and reaches the next level of consumers?
Q42. Which. of the following groups of organisms belong to category of producers?
(a) All green plants, fungi and bacteria
(b) All green plants and certain blue-green algae
(c) Bacteria, fungi and blue-green algae
(d) Certain blue-green algae and fungi