Question

Question 3 Describe briefly:

(a) Arithmetic growth

(b) Geometric growth

(c) Sigmoid growth curve

(d) Absolute and relative growth rates

Class XI Biology Chapter - Plant Growth and Development Page 253

Answer 1

(a) Arithmetic growth :- In arithmetic Growth *only one daughter cell* among the two *further divides* while the *other differentiates* and become mature.

(b) Geometric growth :- In Geometric Growth *both the progeny cells following mitotic division* retain the ability to divide and continue to do so.

(c) Sigmoid growth curve :- The parameter of Growth against time is a sigmoid curve. A Sigmoid growth curve is a characteristic parameter of living organisms growing in a natural environment.

d) Absolute and relative growth rates :-

*1) Absolute Growth rate :-* Total Growth which occur in unit time in plant or any plant part.

*2) Relative Growth rate :-* Total Growth which occur in unit time with respect to initial parameter in plant or any plant part.