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
Logistic 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
I. 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
A broad-based, pyramid shaped age structure is characteristic of a population that is:
(1) Growing rapidly
(2) At carrying capacity
(3) Stable
(4) Shrinking
Carrying capacity for a population is estimated at 500; the population size is currently 400; and rmax = 0.01. What is dN/dt?
(1) 0.01
(2) 0.8
(3) 8
(4) 50
The evolution of the animal immune system was probably driven by:
(1) Herbivores pushing the animals toward extinction
(2) The selective pressures of parasitic and disease organisms
(3) Competition between the animals and their habitats
(4) Symbiosis between the animals and their predators
Which of the following is not entirely true fact?
(1) Competition occurs when closely related species compete for the same resources that are limiting
(2) Totally unrelated species could compete for the same resource
(3) Resources need not be limiting for competition to occur; in interference competition, the feeding efficiency of one species might be reduced due to the interfering and inhibitory presence of the other species, even if resources are abundant.
(4) A complex interplay of interspecific interactions and environmental variability characterizes community structure