Q1. Assertion: The orchid Ophrys employs 'sexual deceit' for pollination.
Reason: One petal of its flower resembles the female of a specific bee species.
Correct Answer: (a)
Page 15: The male bee is attracted... and pseudocopulates with the flower.
Q2. Assertion: Predation is nature's way of transferring energy to higher trophic levels.
Reason: Tigers and sparrows are both examples of predators.
Correct Answer: (a)
The second statement gives examples, but doesn't 'explain' the ecological mechanism of energy transfer.
Q3. Assertion: In a sigmoid curve, the last phase is an asymptote.
Reason: This happens when the population density reaches the carrying capacity.
Correct Answer: (a)
Page 8: Asymptote occurs at carrying capacity.
Q4. An interaction where both species benefit is called:
Q5. Which of the following is correct regarding 'Commensalism'? (i) One species benefits, the other is neither harmed nor benefited. (ii) Orchid on a mango branch is an example. (iii) The clown fish and sea anemone interaction is another example.
Correct Answer: (a)
Definition and examples of commensalism (page 14).
Q6. Which organisms breed only once in their lifetime?
Correct Answer: (b)
Page 9: Some organisms breed only once in their lifetime (Pacific salmon fish, bamboo).
Q7. Verhulst-Pearl Logistic Growth results in which type of curve?
Correct Answer: (b)
Page 8: A plot of N in relation to time (t) results in a sigmoid curve. This type of population growth is called Verhulst-Pearl Logistic Growth.
Q8. In amensalism, one species is ______ and the other is ______.
Q9. Assertion: The tiger census is often based on pug marks and fecal pellets.
Reason: It is very difficult to estimate huge population sizes by direct counting.
Correct Answer: (a)
Page 5: We are mostly obliged to estimate population sizes indirectly... tiger census... is often based on pug marks.
Q10. Assertion: Competition can occur between totally unrelated species.
Reason: Flamingoes and fishes in S. American lakes compete for their common food (zooplankton).
Correct Answer: (a)
Page 11: Firstly, totally unrelated species could also compete for the same resource.
Q11. Match the following for prey defense:
A. Cryptic colouration
(I) Camouflage
B. Distasteful chemical
(II) Monarch Butterfly
C. Poisonous nature
(III) Avoidance by predators
Correct Answer: (a)
Prey defenses (page 11).
Q12. Assertion: Calotropis is avoided by cattle and goats.
Reason: The plant produces highly poisonous cardiac glycosides.
Correct Answer: (a)
Page 11: The plant produces highly poisonous cardiac glycosides and that is why you never see any cattle... browsing on this plant.
Q13. Assertion: The clown fish gets protection by living among sea anemone tentacles.
Reason: Sea anemone tentacles have stinging cells that stay predators away.
Correct Answer: (a)
Page 14: Commensalism example involving sea anemone and clown fish.
Q14. The tiger census in our national parks is often based on:
Correct Answer: (c)
Page 5: The tiger census in our national parks... is often based on pug marks and fecal pellets.
Q15. Assertion: In an age pyramid, an expanding population has a broad base.
Reason: It indicates a high proportion of pre-reproductive individuals.
Correct Answer: (a)
Page 5: Age pyramids for human population.
Q16. Match the population interactions in Column-I with the symbols in Column-II:
Column-I (Interaction)
Column-II (Symbols)
A. Mutualism
(I) +, –
B. Competition
(II) +, +
C. Predation
(III) –, –
D. Commensalism
(IV) +, 0
Correct Answer: (a)
Table 11.1 on page 10.
Q17. Assertion: Predators in nature are described as 'prudent'.
Reason: If a predator is too efficient and overexploits its prey, the prey might become extinct and the predator will follow.
Correct Answer: (a)
Page 11: This is the reason why predators in nature are ‘prudent’.
Q18. Assertion: A species whose distribution is restricted to a small area may expand its range if a competitor is removed.
Reason: This phenomenon is known as 'competitive release'.
Correct Answer: (a)
Page 12: Connell's field experiments showed this with barnacles.
Q19. Match the growth curve variables:
Symbol
Meaning
A. N
(I) Intrinsic rate of natural increase
B. r
(II) Population density
C. K
(III) Carrying capacity
Correct Answer: (a)
Variables from page 7-8.
Q20. Match the following for mutualism:
A. Lichens
(I) Fungi and roots of higher plants
B. Mycorrhizae
(II) Fungus and alga
C. Fig and Wasp
(III) Pollination and oviposition
Correct Answer: (a)
Mutualism examples from page 14-15.
Q21. Assertion: Human beings are able to digest cellulose.
Reason: Cellulose breakdown is assisted by methanogens in the rumen of cattle.
Correct Answer: (a)
Page 7: Do you think we, human beings, are able to digest the cellulose... (implies no, but cattle do).
Q22. Match the biological defences in Column-I with the organisms in Column-II:
Column-I (Defence)
Column-II (Organism)
A. Thorns
(I) Monarch Butterfly
B. Distasteful chemical
(II) Acacia, Cactus
C. Cardiac glycosides
(III) Calotropis
Correct Answer: (a)
Defence mechanisms from page 11.
Q23. Match the following for population growth:
Variable
Definition
A. Natality
(I) Number of births
B. Mortality
(II) Number of deaths
C. Immigration
(III) Individuals coming into habitat
D. Emigration
(IV) Individuals leaving habitat
Correct Answer: (a)
Definitions from page 6.
Q24. Assertion: In interference competition, resources need not be limiting for competition to occur.
Reason: The feeding efficiency of one species might be reduced due to the inhibitory presence of the other.
Correct Answer: (a)
Page 12: Definition of interference competition.
Q25. Match the following for the history of man (intro pages):
A. Homo habilis
(I) 650-800cc
B. Homo erectus
(II) 900cc
C. Neanderthal man
(III) 1400cc
Correct Answer: (a)
Brain capacity data (page 15).
Q26. A population attribute that expresses the proportion of males and females is:
Correct Answer: (c)
Page 4: Another attribute characteristic of a population is sex ratio.
Q27. Assertion: Brood parasitism is seen in the Koel and the Crow.
Reason: The Koel lays eggs in the crow's nest and lets the crow incubate them.
Correct Answer: (a)
Page 13: Brood parasitism in birds example.
Q28. If 8 new lotus plants are added to a current population of 20 through reproduction, the birth rate is:
Correct Answer: (b)
Page 4: Birth rate is calculated as 8/20 = 0.4 offspring per lotus per year.
Q29. In the equation Nt+1 = Nt + [(B + I) – (D + E)], 'I' stands for:
Correct Answer: (b)
Page 6: I stands for Immigration.
Q30. Assertion: Natural selection operates at the population level to evolve desired traits.
Reason: Individual organisms have to cope with a changed environment, but they do not evolve.
Correct Answer: (a)
Page 4: Although an individual... has to cope... it is at the population level that natural selection operates.
Q31. Which of the following is true for 'Carrying Capacity (K)'? (i) It is the maximum number a habitat can support. (ii) Beyond this, no further growth is possible. (iii) it leads to the formation of a sigmoid curve.
Correct Answer: (a)
Carrying capacity and its role in logistic growth (page 8).
Q32. Regarding 'Exponential Growth', which statements are true? (i) Resources (food and space) must be unlimited. (ii) The curve is J-shaped. (iii) The equation is dN/dt = rN.
Correct Answer: (a)
Standard features of exponential growth model (page 7).
Q33. The invasive weed introduced into Australia in the 1920s that caused havoc was:
Correct Answer: (c)
Page 10: The prickly pear cactus introduced into Australia in the early 1920’s caused havoc.
Q34. Which of the following are adaptations of 'Parasites'? (i) Loss of unnecessary sense organs. (ii) Presence of adhesive organs or suckers. (iii) High reproductive capacity.
Correct Answer: (a)
Parasitic adaptations from page 13.
Q35. Identify correct features of the 'Biogas Plant' (Unit VIII context / Figure 8.8): (i) Concrete tank 10-15 feet deep. (ii) Slurry of dung is fed. (iii) Floating cover is placed over the slurry.
Correct Answer: (a)
Based on Figure 8.8 and text from page 8 (156).
Q36. Exponential growth results in which type of curve when plotted against time?
Correct Answer: (c)
Page 7: The above equation describes the exponential... growth pattern... and results in a J-shaped curve.
Q37. Regarding 'Population Attributes', which statements are correct? (i) An individual has births and deaths, but a population has birth and death rates. (ii) Populations have a sex ratio. (iii) An individual is either male or female, but a population is measured in percentages of both.
Correct Answer: (a)
Section 11.1.1 describes attributes like rates and ratios as population-level parameters.
Q38. Assertion: Co-evolution is tight in the fig tree and wasp relationship.
Reason: A given fig species can be pollinated only by its ‘partner’ wasp species and no other.
Correct Answer: (a)
Page 15: The one-to-one relationship ensures co-evolution.
Q39. Match the following for liver fluke:
A. Intermediate host 1
(I) Snail
B. Intermediate host 2
(II) Fish
Correct Answer: (a)
Liver fluke life cycle (page 13).
Q40. The age distribution of a population is graphically represented by:
Correct Answer: (b)
Page 4: If the age distribution... is plotted for the population, the resulting structure is called an age pyramid.
Q41. Assertion: Lichens represent an intimate mutualistic relationship between a fungus and an alga.
Reason: The alga provides energy-yielding carbohydrates to the fungus.
Correct Answer: (a)
Page 14: Definition of mutualism in lichens.
Q42. Who is revered as the Father of Ecology in India?
Correct Answer: (b)
Page 2: Ramdeo Misra is revered as the Father of Ecology in India.
Q43. Identify the correct phylum/group being described: (i) They are phytophagous (feed on plant sap). (ii) Nearly 25 per cent of all these fall into this category. (iii) They are predators for plants.
Correct Answer: (a)
Page 11: Nearly 25 per cent of all insects are known to be phytophagous.
Q44. Regarding 'Parasitism', select the correct statements: (i) Parasites tend to be host-specific. (ii) They often have complex life cycles with intermediate hosts. (iii) Brood parasitism is seen in the crow laying eggs in the koel's nest.
Correct Answer: (a)
The koel (cuckoo) lays eggs in the crow's nest, not the other way around (page 13).
Q45. Match the organisms with their growth parameters:
Column-I
Column-II
A. Norway rat (r)
(I) 0.12
B. Flour beetle (r)
(II) 0.015
C. Human India 1981 (r)
(III) 0.0205
Correct Answer: (a)
Data from page 7.
Q46. Regarding 'Life History Variation', which are correct? (i) Organisms evolve towards the most efficient reproductive strategy. (ii) Pacific salmon breeds only once. (iii) Pelagic fishes produce many small-sized offspring.
Correct Answer: (a)
Life history traits from page 9.
Q47. Assertion: Mycorrhizae are associations between fungi and the roots of higher plants.
Reason: It is a classic example of commensalism.
Correct Answer: (a)
Page 14: Mycorrhizae is an example of Mutualism, not commensalism.
Q48. Match the following for evolutionary theorists:
A. Darwin
(I) Use and disuse of organs
B. Lamarck
(II) Natural selection
C. Hugo de Vries
(III) Saltation
Correct Answer: (a)
Theories from page 9-10 (118-119).
Q49. Which of the following is correct regarding 'Age Pyramids'? (i) The shape reflects the growth status of the population. (ii) Expanding populations have more post-reproductive individuals. (iii) Stable populations have equal proportions of pre-reproductive and reproductive individuals.
Correct Answer: (a)
Expanding populations have more pre-reproductive individuals; stable ones have equal proportions (page 4-5).
Q50. Match the following for commensalism (epiphytes):
A. Orchid
(I) Epiphyte
B. Mango tree
(II) Support (Host)
Correct Answer: (a)
Epiphyte example (page 14).
Q51. The starfish Pisaster is an important predator in which community?
Correct Answer: (c)
Page 11: In the rocky intertidal communities of the American Pacific Coast the starfish Pisaster is an important predator.
Q52. Identify the correct statements for 'Logistic Growth': (i) It is called Verhulst-Pearl Logistic Growth. (ii) A population starts with a lag phase. (iii) It eventually reaches an asymptote when N = K.
Correct Answer: (a)
Standard features of logistic growth model (page 8).
Q53. Assertion: Parasites may render the host more vulnerable to predation.
Reason: Parasites make the host physically weak.
Correct Answer: (a)
Page 13: Parasites may reduce host survival by making them weak.
Q54. Identify the correct statements regarding 'Competition': (i) It is a potent force in organic evolution. (ii) Abingdon tortoise became extinct due to goats. (iii) Closely related species always exclude each other.
Correct Answer: (a)
Species may evolve mechanisms like resource partitioning to co-exist rather than exclude (page 12).
Q55. Identify correct statements for 'Resource Partitioning': (i) It promotes co-existence rather than exclusion. (ii) MacArthur showed this in warblers. (iii) Species choose different foraging patterns.
Correct Answer: (a)
Definition and MacArthur's study (page 12).
Q56. Match the following for interspecific interactions:
Combination
Interaction
A. (–, –)
(I) Competition
B. (+, –)
(II) Predation/Parasitism
C. (+, 0)
(III) Commensalism
Correct Answer: (a)
Table 11.1 on page 10.
Q57. Match the natural selection patterns (Figure 6.8 / 11.3 context):
Q58. Match the following for plant chemical defenses:
A. Cardiac glycosides
(I) Calotropis
B. Nicotine, Caffeine, Opium
(II) Commercial extraction / Defense
Correct Answer: (a)
Chemical defenses from page 11.
Q59. Which factor might contribute more significantly to population growth than birth rates in a newly colonised habitat?
Correct Answer: (c)
Page 6: For instance, if a new habitat is just being colonised, immigration may contribute more significantly.
Q60. Which of the following are correct regarding 'Predation'? (i) Predators keep prey populations under control. (ii) Introduction of exotic species can lead to invasiveness due to lack of natural predators. (iii) Predators help in maintaining species diversity.
Correct Answer: (a)
Ecological roles of predators (page 10-11).
Q61. Assertion: Resource partitioning allows species to avoid competition.
Reason: Species choose different times for feeding or different foraging patterns.
Correct Answer: (a)
Page 12: MacArthur showed this with five species of warblers.
Q62. Match the interactions with their names:
Column-I (Combination)
Column-II (Name)
A. (–, 0)
(I) Mutualism
(II) Amensalism
B. (+, 0)
(III) Commensalism
C. (+, +)
(IV) Parasitism
D. (+, –)
Correct Answer: (a)
Table 11.1 on page 10.
Q63. The 'r' value for the Norway rat is:
Correct Answer: (c)
Page 7: For the Norway rat the r is 0.015.
Q64. Match the following for parasite characteristics:
Q65. Assertion: Growth of a population is ultimately limited by the carrying capacity of the environment.
Reason: In nature, resources are finite and eventually become limiting.
Correct Answer: (a)
Page 16: Logistic growth model description in summary.
Q66. Regarding the 'Law of Dominance' (Mendel's laws mentioned in intro): (i) Characters are controlled by factors. (ii) Factors occur in pairs. (iii) One member of a dissimilar pair dominates the other.
Correct Answer: (a)
Mendelian principles summary from page 9 (59).
Q67. Which statement is true for the 'Intrinsic rate of natural increase (r)'? (i) It is a measure of the inherent potential of a population to grow. (ii) It is used to assess impacts of biotic/abiotic factors. (iii) It is the difference between birth and death rates (b-d).
Correct Answer: (a)
Definitions from page 7.
Q68. The essence of biological understanding is to know how organisms interact with other organisms and physical habitats as a group, known as:
Correct Answer: (b)
Page 1: The essence is to know how organisms interact... and hence behave like organised wholes, i.e., population, community, etc.
Q69. Nature’s limit for supporting a maximum possible number of a species in a habitat is called:
Correct Answer: (c)
Page 8: Let us call this limit as nature’s carrying capacity (K) for that species.
Q70. A population density measured in terms of percent cover or biomass is preferred when:
Correct Answer: (b)
Page 5: Stating density of banyan relative to carrot grass in numbers underestimates its role; percent cover/biomass is more meaningful.
Q71. Regarding 'Mutualism', identify the correct statements: (i) Both interacting species benefit. (ii) Mycorrhizae are associations between fungi and plant roots. (iii) The fig tree provides food for wasp larvae.
Correct Answer: (a)
Definition and examples of mutualism (page 14-15).
Q72. Match the following for competition in barnacles:
Correct Answer: (a)
Classification of parasites from page 13.
Q74. Match the following for competition examples:
A. Abingdon tortoise
(I) Goats in Galapagos
B. Balanus and Chathamalus
(II) Rocky sea coasts of Scotland
C. Warblers
(III) Resource partitioning
Correct Answer: (a)
Competition evidence from page 12.
Q75. Which of the following processes contributes to a decrease in population density?
Correct Answer: (c)
Page 6: Mortality and emigration contribute to a decrease in population density.
Q76. Assertion: Gause’s ‘Competitive Exclusion Principle’ states that closely related species cannot co-exist indefinitely if resources are limiting.
Reason: The competitively inferior one will be eliminated eventually.
Correct Answer: (a)
Page 12: Definition of Gause’s principle.
Q77. Match the following for mutualistic pollinators:
Q78. Which of the following is correct? (i) All locomotions are movements. (ii) Evolution is a stochastic process. (iii) Humans use limbs for both posture change and locomotion.
Correct Answer: (a)
Standard biological facts from the chapter.
Q79. Ramdeo Misra helped establish the National Committee for Environmental Planning and Coordination in which year?
Correct Answer: (b)
Page 2: Due to his efforts, the Government of India established the National Committee for Environmental Planning and Coordination (1972).
Q80. Regarding 'Haplodiploid sex-determination' (Unit VII context): (i) Males have half the number of chromosomes than females. (ii) Seen in honey bees. (iii) Males produce sperms by mitosis.
Correct Answer: (a)
Data from the human reproduction/genetics context of the intro pages (124/125 context).
Q81. Match the following for age pyramids:
A. Expanding
(I) Pre-reproductive > Reproductive
B. Stable
(II) Pre-reproductive = Reproductive
C. Declining
(III) Pre-reproductive < Reproductive
Correct Answer: (a)
Age pyramid interpretation (page 5).
Q82. Match the following for plant life cycles:
A. Pacific salmon fish
(I) Breed only once
B. Bamboo
(II) Breed only once
C. Most birds
(III) Breed many times
Correct Answer: (a)
Life history traits (page 9).
Q83. The Monarch butterfly is distasteful to its predator (bird) because of a chemical acquired during which stage?
Correct Answer: (c)
Page 11: The butterfly acquires this chemical during its caterpillar stage by feeding on a poisonous weed.
Q84. Match the following for population growth models:
A. J-shaped
(I) Exponential
B. S-shaped (Sigmoid)
(II) Logistic
Correct Answer: (a)
Descriptions from page 7-8.
Q85. Which level of biological organisation is basically concerned with interactions among organisms and between the organism and its physical environment?
Correct Answer: (b)
Page 4: Ecology is a subject which studies the interactions among organisms and between the organism and its physical (abiotic) environment.
Q86. Identify the correct statements for 'Population Growth': (i) Natality and Immigration increase population density. (ii) Mortality and Emigration decrease population density. (iii) Under normal conditions, immigration is the most important factor.
Correct Answer: (a)
Under normal conditions, births and deaths are most important; immigration is secondary (page 6).
Q87. Assertion: Endoparasites have complex life cycles.
Reason: They are extremely specialized in their site of living inside the host body.
Correct Answer: (a)
Page 13: Endoparasite life cycles are more complex because of extreme specialisation.
Q88. Correct statements for 'Ramdeo Misra' include: (i) He establishing teaching and research in ecology at BHU. (ii) He formulated the first postgraduate course in ecology in India. (iii) He supervised over 50 Ph.D. scholars.
Correct Answer: (a)
Biographical details from page 2.
Q89. Assertion: Ectoparasites live inside the host body.
Reason: The life cycles of endoparasites are more complex because of their extreme specialisation.
Correct Answer: (a)
Page 13: Ectoparasites feed on the external surface; endoparasites live inside the body.
Q90. Assertion: Logistic growth is considered a more realistic model in nature.
Reason: Resources for growth for most animal populations are finite and become limiting.
Correct Answer: (a)
Page 9: Since resources... are finite and become limiting... the logistic growth model is considered a more realistic one.
Q91. The 'r' value for the flour beetle is:
Correct Answer: (c)
Page 7: For the flour beetle it is 0.12.
Q92. If 4 fruitflies in a laboratory population of 40 died in a week, the death rate is:
Correct Answer: (a)
Page 4: Death rate is calculated as 4/40 = 0.1 individuals per fruitfly per week.
Q93. Assertion: Parasites tend to co-evolve with their hosts.
Reason: Hosts evolve mechanisms for resisting the parasite, and parasites evolve to counteract them.
Correct Answer: (a)
Page 13: Many parasites have evolved to be host-specific... both host and the parasite tend to co-evolve.
Q94. In 1981, the 'r' value for the human population in India was:
Correct Answer: (b)
Page 7: In 1981, the r value for human population in India was 0.0205.
Q95. Match the following for commensalism:
Column-I (Species A)
Column-II (Species B)
A. Orchid epiphyte
(I) Mango tree
B. Barnacles
(II) Whale
C. Cattle Egret
(III) Grazing Cattle
D. Sea Anemone
(IV) Clown Fish
Correct Answer: (a)
Examples of commensalism from page 14.
Q96. Select correct statements for 'Co-evolution': (i) Seen in the fig-wasp relationship. (ii) Seen in the orchid-bee relationship. (iii) Evolutions of the flower and its pollinator species are tightly linked.
Correct Answer: (a)
Principles of co-evolution from page 15.
Q97. Identify correct facts for 'Amoeboid Movement' (Unit VIII intro / Page 2): (i) Effected by pseudopodia. (ii) Cytoskeletal elements like microfilaments are involved. (iii) Seen in macrophages and leucocytes.
Correct Answer: (a)
Based on the introduction/Unit 5 logic provided in previous chapters (though page 1/2 of this PDF mentions individual interactions).
Q98. Which is true for the 'Ganga Action Plan'? (i) Initiated to save major rivers from pollution. (ii) Proposed building a large number of sewage treatment plants.
Correct Answer: (a)
Environmental plans from page 7 (155).
Q99. Match the following for history of man settlement:
A. 18,000 years ago
(I) Cave Art
B. 10,000 years ago
(II) Agriculture
Correct Answer: (a)
Timeline from page 16.
Q100. Select correct statements for 'Niche' (implied in interaction sections): (i) No two species can co-exist indefinitely if they compete for the same limiting resources. (ii) This is Gause's Competitive Exclusion Principle.