1. Vivipary is characteristic of

A. mesophytes
B. xerophytes
C. hygrophytes
D. halophytes
Answer :   halophytes
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2. Between which among the following, the relationship is not an example of commensalism?

A. Female wasp and fig species
B. Orchid and the tree on which it grows
C. Cattle egret and grazing cattle
D. Sea anemone and clown fish
Answer :   Female wasp and fig species
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3. Keystone species in an ecosystem are those

A. present in maximum number
B. that are most frequent
C. attaining a large biomass
D. contributing to ecosystem properties
Answer :   contributing to ecosystem properties
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4. What is a keystone species?

A. A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival
B. A common species that has plenty of biomass, yet has a fairly low impact on the community's organization
C. A rare species that has minimal impact on the biomass and on other species in the community
D. A dominant species that constitutes a large proportion of the biomass and which affects many other species
Answer :   A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival
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5. Asymptote in a logistic growth curve is obtained when :

A. $$K = N$$
B. $$K > N$$
C. $$K < N$$
D. The value of $$'r'$$ approaches zero
Answer :   $$K = N$$
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6. Praying mantis is a good example of

A. warning colouration
B. social insects
C. camouflage
D. mullerian mimicry
Answer :   camouflage
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7. All of the following statements concerning the Actinomycetes filamentous soil bacterium Frankia are correct except that Frankia :

A. Can induce root nodules on many plant species
B. Cannot fix nitrogen in the free-living state
C. Forms specialized vesicles in which the nitrogenase is protected from oxygen by a chemical barrier involving triterpene hopanoids
D. Like Rhizobium, it usually infects its host plant through root hair deformation and stimulates cell proliferation in the host's cortex
Answer :   Cannot fix nitrogen in the free-living state
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8. Cuscuta is an example of

A. ectoparasitism
B. brood parasitism
C. predation
D. endoparasitism
Answer :   ectoparasitism
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9. Gause's principle of competitive exclusion states that :

A. more abundant species will exclude the less abundant species through competition
B. competition for the same resources excludes species having different food preferences
C. no two species can occupy the same niche indefinitely for the same limiting resources
D. larger organisms exclude smaller ones through competition
Answer :   no two species can occupy the same niche indefinitely for the same limiting resources
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10. In which of the following interactions both partners are adversely affected ?

A. Predation
B. Parasitism
C. Mutualism
D. Competition
Answer :   Competition
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