(1) A - II, B - I, C – III

(2) A - II, B - IV, C - III

(3) A - III, B - IV, C – I

(4) A - I, B - II, C - IV

The density of a population in a given habitat during a given period, fluctuates due to changes in four basic processes. On this basis fill up A and B boxes in the given diagram with correct options:

(a) A = Natality + Immigration, B = Mortality + Emigration

(b) A = Natality + Mortality, B = Immigration + Emigration

(c) A = Birth rate + Death rate, B = Migration + Emigration

(d) A = Natality + Emigration, B = Mortality + Immigration

Population density will increase if

1.  Number of births and number of deaths increase.

2.  Number of births and number of immigrants is high.

3.  Number of immigrants and number of deaths is high.

4.  Number of births and number of immigrants is low.

Which the following pairs is wrongly matched while remaining three are correct

1. Allen’s rule – Mammals with shorter ears and limbs in colder area

2. Expanding population – High number of individual at pre-reproductive stage

3. Population density increasing – (B + I) < (D + E)

4. Carrying capacity – Logistic growth.

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

1. 10         

2. 15           

3. 05           

4. zero

Population growth of a species is not related to which of the following parameters?
(1) Nt + 1 = Nt + [(B + I) − (D + E)]

(2) Out of the four basic processes effecting population growth three leads to increase in population size

(3) For a newly colonised habitat immigration plays major role than birth rate

(4) Under normal conditions, natality and mortality are the most important factors

The biological community can have

1. An isolated population of plants which doesn't depend on animals and microbes

2. An isolated population of animals which doesn't depend on plants and microbes

3. An isolated population of microbes which doesn't depend on plants and animals

4. No isolated population is possible there.

Which of the following is not a factor that would limit the growth of a population?

(1) Food shortage

(2) Immigration

(3) Disease

(4) Famine

Triangular age pyramid represents
1. Expanding population.
2. Declining population.
3. Mature population.
4. Both 1. and 3.

A country with a high rate of population growth took measures to reduce it. The figure below shows age sex pyramids of populations. A and B twenty years apart. Select the correct interpretation about them.

Interpretations

1. 'A' is more recent and shows slight reduction in the growth rate

2. 'B' is earlier pyramid and shows stabilized growth rate

3. 'B' is more recent showing that population is very young

4. 'A' is the earlier pyramid and no change has occured in the growth rate