Back

12 Biology Organisms and Populations - Set No : 32 Question No :4

Question No : 4
               Which option is correct for curve  and ?Equation for    equation for        Type of                       Type ofCurve (a)          curve (b)              curve (a)                    curve (b)     

                a)                    Exponential curve   Logistic curve          b)                          Exponential curve   Logistic curve     

                c)                          S-shaped curve        J-shaped curve          d)          Both (b) and (c)     

Answer No : 4
     (b)Exponential growth curve is also called J-shaped curve or geometric growth curve.Logistic curve is also called sigmoid growth curve J-shaped curve.Exponential Growth Model When the resources availability is unlimited in the habitat, the population grows in an exponential or geometric fashion. As resources are unlimited than there is no inhibition from crowding.The equation is;  Birth rate,  Death rate Population density, = Rate of change of populationLet (b-d) = r, then the equation is,  Intrinsic rate of natural increaseWhen a population shows exponential growth, the curve plotted with  in relation to time, assume J shapeIn this there is no fix carrying capacityLogistic Growth Model No population can continue to grow exponentially, as the resource availability become limiting at certain point of time. Logistic growth model have fixed carrying capacityIt is described by the equation   Rate of change of population densityN = Population density at timeN = Population densityr = Intrinsic rate of natural increaseK = Carrying capacityPopulation growth curve  when resources are not limiting. Plot is exponential or geometrical curve . When resources are limiting the growth, plot is logistic‘’ is carrying capacity     

Back