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Following four types of species were observed in a community:

A. Species A has a large effect on community because of its abundance.

B. Species B has a large role in community out of proportion to its abundance.

C. Status of species C provides information on the overall health of an ecosystem.

D. Significant conservation resources are allocated to species D which is single, large and instantly recognizable.

According to above description, species A, B, C, and D are called respectively,

• Dominant, Keystone, Indicator and Flagship

• Keystone, Flagship, Dominant and Indicator.

• Keystone, Dominant, Indicator and Flagship.

• Flagship, Dominant, Keystone and Indicator

The diagram represents the competition between species 1 and species 2 according to Lotka-Volterra model of competition.

Given the conditions in the diagram, the predicted outcome of competition is

• Unstable coexistence between species 1 and 2 because K₁ > K₂/β and K₂ > K₁/α.

• Unstable coexistence between species 1 and 2 because K₁ < K₂/β and K₂ < K₁/α.

• Stable coexistence between species 1 and 2 because K₁ > K₂/β and K₂ > K₁/α.

• Stable coexistence between species 1 and 2 because K₁ < K₂/β and K₂ < K₁/α.

The possible relationships between level of disturbance and species diversity in a biological community are that species diversity.

A. is unaffected by disturbance.

B. is highest at intermediate levels of disturbance.

C. decreases exponentially with increasing levels of disturbance.

D. starts decreasing only at higher levels of disturbance.

An example of the species interaction called commensalism is

• nitrogen-fixing bacteria in association with legume plant roots.

• microbes in living human gut.

• female mosquito deriving nourishment from human blood.

• orchid plant growing on the truck of a mango tree.

What parameter, plotted on Y-axis against generation time, would yield the curve shown in the figure?

• Survivorship

• Body size

• Lifespan

• Intrinsic rate of increase

In which ecosystem is the detrital pathway of energy flow most important?

• Lakes

• Grasslands

• Tropical rain forests

• Oceans

Individuals with greater mass have a smaller surface area to volume ratio, which helps to conserve heat. This is known as

• Leibig's rule

• Cope's rule

• Gloger's rule

• Bergmann's rule

The dynamics of any subpopulation within a metapopulation differs from that of a normal population in that the

• birth rates are lower than the death rates.

• death rates are lower than the birth rates.

• immigration and emigration rates are significantly higher.

• immigration and emigration rates are negligible.

The general relation between generation time (T) and population growth rate (r) is described by the equation

• lnr = lna - b ln T

• r = a - b  T

• lnr = lna + b ln T

• r = a + b T

Which of the following is likely to contribute to the stability of an ecosystem?

• High number of specialists

• Fewer number of functional links

• More omnivores

• Linear rather than reticulate food webs