Annual migration does not occur in the case of
1. Salmon
2. Siberian crane.
3. Salamander.
4. arctic tern.

Exponential population growth is represented by
1. dt/dn=rN
2. dN/rN= dt
3. rN/dN= dt
4. dN/dt = rN

Praying mantis is a good example of
1. mullerianmimicary.
2. warning colouration.
3. social insect
4. camouflage.

The population of an insect species shows an explosive increase in number during rainy season followed by its disappearance at the end of the season. What does this show?

Graph below is a diagrammatic representation of response of organisms to biotic factors. What do a,b,c represent respectively?


1. Partial regulator, conformer, regulator
2. Regulator, conformer, Partial regulator
3. Conformer, regulator, Partial, regulator
4. Regulator, Partial conformer, regulator

What type of human population is represented by the following age pyramid?

1. Expanding population
2. Vanishing population
3. Stable population
4. Declining population

The logistic population growth is expressed by the equation:
1. \(\dfrac{dN}{dt} = rn \left(\dfrac{N - K}{N}\right)\)
2. \(\dfrac{dt}{dN} = Nr \left(\dfrac{K - N}{K}\right)\)
3. \(\dfrac{dN}{dt} = rN \left(\dfrac{K - N}{K}\right)\)
4. \(\dfrac{dN}{dt} = rN\)

Cuscuta is an example of
1. predation.
2. endoparasitism.
3. ectoparasitism.
4. brood parasitism.

A biologist studied the population of rats in a barn. He found that the average natality was 250, average mortality 240, immigration 20, and emigration 30. The net increase in population is:

A sedentary sea anemone gets attached to the sheel lining of hermit crab. The association is
1. ectoparasitism
2. symbiosis.
3. commensalism.
4. amensalism.