Which of the following statement is false with respect to adaptations?
(1) Many xerophytic plants have thick cuticle on leaf epidermis, sunken stomata

(2) Some xerophytic plants have special photosynthetic pathway (CAM) that enables their stomata close during day

(3) Opuntia has spines (modified leaves), photosynthetic phylloclade (stem)

(4) All adaptations are genetically fixed all organisms

Density of a population (D) is:

(1) $D=\frac{D \left(size\right)}{W (wt.)}$                           

(2) $\mathrm{D}=\frac{\mathrm{S} \left(\mathrm{space}\right)}{\mathrm{N} \left(\mathrm{number}\right)}$

(3)  $D=\frac{N \left(number\right)}{S \left(space\right)}$                           

(4) None of the above

If the age distribution (percent individuals of a given age or age group) is plotted for population, the resulting structure is called:

(1) Survivorship curve                       

(2) Life table

(3) Age pyramid                                

(4) Logistic model

The age distribution of a population is determined by:

(1) Timing of birth

(2) Timing of death

(3) The rate at which the population is growing

(4) All are correct

What four factors define population growth?

1. Births; deaths, immigration, emigration

2. Survivorship, age-specific mortality, fecundity, death rate

3. Mark-recapture, census, quadrate sampling, transects

4. Age-specific birth rate, metapopulation structure, quadrate, ecotone

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 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

Exponential growth occurs when there is:

(1) Asexual reproduction only            

(2) Sexual reproduction only

(3) No inhibition from crowding         

(4) A fixed carrying capacity

The logistic population growth model, dN/dt = rN (K - N/K), describes a populations growth when an upper limit to growth is assumed. This upper limit to growth is known as the population's ________, and as N gets larger, dN/dt ________:

(1) Biotic potential, increases            

(2) Biotic potential, decreases

(3) Carrying capacity, increases                  

(4) Carrying capacity, decreases

In a population growth rate curve the lag phase represents the period when a population is adjusting to a new environment.
II. In a population growth rate curve the steepest part of growth phase represents the period when a population is growing exponentially.
III. In the stationary phase of a population growth rate curve the population is in dynamic equilibrium
IV. Human have changed the carrying capacity of the earth.
(1) All are correct           

(2) I, II, III             

(3) II, III               

(4) I, IV