Study the population growth curves shown above
(i) Identify curves` 'a' and 'b'`.
(ii) Mention the conditions responsible for the curves 'a' and 'b' respectively.
(iii) Give the necessary eqution for the curve 'b'

Explanation

(i) a = when resources are not limlting the growrh,

Plot exponental growth curve.
`(dN)(dt)=rN`
b = when resources are limiting the growth, Plot is logistic growth curve.
`(dN)/(dt) = rN ((K-N)/(K))`
(ii) In nature a given habitat has enough resources to support a maximum possible number, beyond which no further growth is possible.
Aa population growing in a habitat with limited resources shows a lag phase which is followed by phases of acceleration and declaration and finally an asymptote.
(iii) `(dN)/(dt) = rN ((K-N)/(K))`
N = Population density at time (t)
r = Instrinsic rate of natural increase
K = carring capacity.