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1. The upper part of an aquatic ecosystem contains

(A) Nekton

(B) Plankton

(C) Benthos

(D) both (1) and (2)

Answer: Plankton

2. In a day, How many times an individual inspire and expire (breathing)?

(A) 10,000

(B) 20,000

(C) 40,000

(D) 50,000

Answer: 40,000

3. What percentage of total metabolic energy is produced through fermentation of lactic acid?

(A) 80%

(B) 70%

(C) 100%

(D) 40%

Answer: 70%

4. Which adaptation is observe only in xerophytes ?


(B) Hatch-Slack


(D) C3 cycle

Answer: CAM

5. Which of the following option is correct for CO2 absorption in CAM?

(A) During night

(B) Only at midnight

(C) During day time

(D) Morning

Answer: During night

6. Few statements are given below in reference with Thermodynamics, Which of the following option shows all correct statements for it?
(i)Amount of energy is constant.
(ii)During transfer of energy some amount of energy is converted in to heat.
(III) Free energy= energy which can do work.
(IV) At each trophic level amount of stored energy reduces.

(A) (I) and(II)

(B) (III) and (iv)

(C) (i) and (iv)

(D) All of the given

Answer: All of the given

7. Food chain always start with producer, which of the following is an exceptional to the given statement.

(A) Rat

(B) Fox

(C) Lion

(D) Earth – worm

Answer: Earth – worm

8. X is released in Halophytes and Y is source of it, Z process occurs in- estuary, then What does x,y,z indicate?

(A) Potassium Y – rocks Z- Biological magnification

(B) X – DDT Y – Water

(C) Y- Biological magnification

(D) None of this

Answer: Y- Biological magnification

9. What is incorrect for oxygen?

(A) Most of the metabolic energy is produced by it.

(B) Plants are included in the organisms producing it

(C) It is essential for all the organisms

(D) Its proportion in water is 90%

Answer: It is essential for all the organisms

10. What does pyramid of Biomass of an ecosystem indicate in

(A) Number of species in each trophic level

(B) Number of organisms in each trophic level

(C) Organisation of tissue of each trophic level

(D) All of the given

Answer: Organisation of tissue of each trophic level

11. Name the term which defines the ability of community return to its original state after being displaced?

(A) Dispersed

(B) Clumped

(C) Resistance

(D) Resilience

Answer: Resilience

12. Which of the following is a diversity index?

(A) Upright index

(B) Inverted index

(C) Bell shaped index

(D) Simpson’s index

Answer: Simpson’s index

13. On an ecological time scale, the process of directional change in community composition is known as ____________

(A) Keystone species

(B) Succession

(C) Guild

(D) Population

Answer: Succession

14. Climax community is the end point of the succession

(A) True

(B) False

Answer: True

15. Which of the following selection pressure is obtained in late succession stage?

(A) K- selection

(B) R- selection

(C) E-selection

(D) L- selection

Answer: K- selection

16. What is the entropy of the early succession community?

(A) Medium

(B) Low

(C) High

(D) Very high

Answer: High

17. Name the succession in which development of the biotic community starts after the destruction of an existing community?

(A) Climax

(B) Seral

(C) Primary succession

(D) Secondary succession

Answer: Secondary succession

18. Which of the following succession processes describes the development of bare area without any form of life?

(A) Dispersed

(B) Clumped

(C) Ecesis

(D) Nudation

Answer: Nudation

19. Which of the following factor is NOT responsible for autotrophic succession?

(A) Climate

(B) Soil erosion

(C) Man

(D) Microorganisms

Answer: Microorganisms

20. Name the scientist who had described the term climax.

(A) Linneus

(B) Clement

(C) Puri

(D) Cowles

Answer: Cowles

21. Which option is correct for the given information?
Ecosystem is an outcome of an interaction between all living components and non- living components of Environment.
GPP= NPP- loss due to respiration
Primary productivity is measured in dry biomass.





Answer: TTF

22. In one forest maximum 500 lions can be allowed with than what does 500 indicate?

(A) Maximum birth rate

(B) Population of lion

(C) Carrying Capacity of Population

(D) Related birth rate

Answer: Carrying Capacity of Population

23. At which vital index population is stable?

(A) 1

(B) 0

(C) Infinitive

(D) 100

Answer: 100

24. In any of the ecosystem man can be

(A) Primary Consumer Consumer

(B) Secondary

(C) Producer

(D) a & c

Answer: a & c

25. If earth is considered a unit region then biosphere can be compared to

(A) Eco-System

(B) Population

(C) Biotic Community

(D) Species

Answer: Biotic Community

26. If earth is considered a unit region then it can be compared to

(A) Eco-System

(B) Population

(C) Biotic Community

(D) Species

Answer: Eco-System

27. Who accepts the nutrient released in environment by decomposer?

(A) Consumers

(B) Producers

(C) Secondary Consumers

(D) None of the given

Answer: Producers

28. If herbivores are “5” in number in the given food chain then, what will be the total number of trophic layers in the it?

(A) 7

(B) 8

(C) 5

(D) can not be predicted

Answer: can not be predicted

29. Which organism provided useable phosphate from dead organisms?

(A) Fungi, Bacteria

(B) Fungi , Algae

(C) Bacteria, Algae

(D) Bacteria, Fungi

Answer: Bacteria, Fungi

30. What is an Original Source of energy flow in any food chain?

(A) Sun

(B) Produces

(C) Primary

(D) None

Answer: Produces

31. Name the type of community which is maintained by the man or his domestic animals.

(A) Climatic

(B) Edaphic

(C) Disclimax

(D) None of these

Answer: Disclimax

32. Who developed the polyclimax theory?

(A) Daubenmire

(B) R.H Whittaker

(C) Clement

(D) Tansley

Answer: Tansley

33. Which of the following term is given to the process of successful establishment of the species?

(A) Ecesis

(B) Aggregation

(C) Nudation

(D) Competition

Answer: Ecesis

34. What is the effect on biodiversity when we move from pole to equator?

(A) High

(B) Increases

(C) Decreases

(D) Remains same

Answer: Increases

35. Population of which of the following will be highest in the food chain?

(A) Decomposer

(B) Primary Producer

(C) Photosynthetic organism

(D) Secondary consumers

Answer: Photosynthetic organism

36. Who is food component of the grazing food chain?

(A) Consumer

(B) Decomposer

(C) Photosynthetic living organism

(D) Photosynthetic consumers

Answer: Decomposer

37. System resulting from interaction of all the known living factors and populaton of all the species of a unit area is

(A) Ecology

(B) Genetics

(C) Science of plants and animal

(D) Ecosystem

Answer: Ecosystem

38. In which of the following plants are included in any food chain?

(A) Primary Producer

(B) primary comsumer

(C) Primary predator& producer

(D) Primary decomposer

Answer: Primary Producer

39. Which of the following is the correct statement for food chain?

(A) Every chain formed by nutritional relations is used to understand energy flow

(B) Energy component of the food chain forms trophic level

(C) Inter- relation amongest different food chain froms food web

(D) All of the given

Answer: All of the given

40. Which of the following uses maximum energy?

(A) Primary consumer

(B) Secondary consumer

(C) Decomposer

(D) Primary Producers

Answer: Primary Producers

41. Through, which of the following, energy enters in an ecosystem?

(A) Herbivores

(B) Producer

(C) Decomposer

(D) Primary producers

Answer: Producer

42. Why is algae placed in first place of food chain?

(A) Algae is first to synthesize food

(B) Algae is first to consume food

(C) Every living organism can utilize food

(D) None of the given

Answer: Algae is first to synthesize food

43. In which of the following wheat eating pegions included ?

(A) Decomposer

(B) Primary consumer

(C) primary producers

(D) secondary consumer

Answer: Primary consumer

44. which of the following is placed in upper most (highest) level of ecological pyramids.

(A) Herbivores

(B) Carnivors

(C) Primary and Secondary Producers

(D) Primary and Secondary consumer

Answer: Carnivors

45. As we proceed in food chain, bio-mass

(A) Remain Same

(B) Decreases

(C) Increases

(D) Initially same and later keep decreasing

Answer: Decreases

46. In ecosystem the source of energy is


(B) Sun

(C) The Green plant

(D) Sugar

Answer: The Green plant

47. Who is primary consumer of biotic community ?

(A) Herbivores/ Grazing animal

(B) Omnivores

(C) Scavengers

(D) Carnivores

Answer: Herbivores/ Grazing animal

48. In which of the following weeds are placed?

(A) Primary producers

(B) Secondary consumer

(C) Primary consumer

(D) Decomposer

Answer: Primary producers

49. When does the energy flow start in an ecosystem ?

(A) When material cycle starts

(B) When sun rises

(C) When any living organism gain food

(D) When light energy is converted in chemical energy

Answer: When sun rises

50. Which of the following option is correct for storage place phosphorus and nitrogen respectively?

(A) Consumer

(B) Parental rock and environment

(C) Environment and producers

(D) Environment and parental rock

Answer: Parental rock and environment

51. Which of the following is trophic level of the orchid staying on mango tree?

(A) First

(B) Tertiary/ Third

(C) Second

(D) Fourth

Answer: First

52. Which age group in pyramid indicate less reproductive potential?

(A) Bell shaped

(B) Triangular

(C) Inverted Bell shaped

(D) All of them have equal (same) potential

Answer: Inverted Bell shaped

53. It is correct for ecosystem

(A) (Plants, Animals, Microorganisms) + Abiotic environment

(B) Community formed by various species present in a particular region

(C) Animal, plants and micro- organisms

(D) Abiotic factors

Answer: (Plants, Animals, Microorganisms) + Abiotic environment

54. What is the original source of energy for the living organisms?

(A) Carbohydrate

(B) Sun light


(D) Lipid

Answer: Sun light

55. In which of the following curd eating people are included?

(A) Producer

(B) First

(C) Tertory

(D) Second

Answer: Producer

56. The functional efficiency of ecosystem is effected when decomposers are removed from it, because

(A) Energy flow will stop

(B) Rest components decomposition will become faster

(C) Herbivors will not get sun light

(D) Flow of nutrient will stop

Answer: Flow of nutrient will stop

57. From which of the following detritus food chain will start ?

(A) Algae

(B) Bacteria

(C) Protozoa

(D) Virus

Answer: Bacteria

58. Which of the following is gaseous cycle?
(1) Sulphur cycle
(3) Phosphorous cycle
(2) Carbon cycle
(4) Nitrogen cycle

(A) 1

(B) 1,2

(C) 3, 4

(D) 1,3,4

Answer: 3, 4

59. At Each trophic level, in which form energy is lost ?

(A) Heat

(B) Chemical

(C) Light

(D) None

Answer: Heat

60. Which Source of eutrophication is the modern source of phosphorus ?

(A) Detergent

(B) Fertilizer

(C) Faecal of animal

(D) Rivers

Answer: Detergent

61. Lincoln index measures

(A) Population mortality rate

(B) Population natality rate

(C) Population size

(D) Population density

Answer: Population size

62. Allelopathy refers to

(A) Inhibition of growth of one species by another by the production of toxins

(B) Inhibition of sporulation of pathogen by the host

(C) Altering the reproductive cycle of one organism by another

(D) Inhibition of growth of one species by another by preventing reproduction

Answer: Inhibition of growth of one species by another by the production of toxins

63. The ratio between energy flow at different points in a food chain is known as

(A) Ecological capacity

(B) Ecological efficiency

(C) Ecological assimilation

(D) Ecological potential

Answer: Ecological efficiency

64. The ability of a population to increase under ideal environmental conditions is called

(A) Natality

(B) Carrying capacity

(C) Biotic potential

(D) Absolute natality

Answer: Biotic potential

65. In an ecosystem, the energy flow is always

(A) Always unidirectional

(B) Always bidirectional

(C) In any direction

(D) Always down directional

Answer: Always unidirectional

66. In thermal stratification, the middle region which shows vertical temperature change is called

(A) Mesolimnion

(B) Epilimnion

(C) Metalimnion

(D) Hypolimnion

Answer: Metalimnion

67. Select a non-denitrifying bacteria

(A) Pseudomonas aeruginosa

(B) Thiobacillus

(C) Thiobacillus denitrificans

(D) Bacillus ramosus

Answer: Bacillus ramosus

68. Which one is a ‘K’ selected species?

(A) Aspergillus

(B) Human

(C) Taraxacum

(D) Grass

Answer: Human

69. All species of Lemur are endemic to which area?

(A) Madagascar

(B) Seychelles Island

(C) Galapagos Island

(D) New Caledonia

Answer: Madagascar

70. Which of the following helps in absorbtion of phosphorous?

(A) Leaves

(B) Mycorriza

(C) Root

(D) Stem

Answer: Mycorriza

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