Question

Which of the following statements are correct regarding the type of growth represented by the diagram?


1. It is observed at initial stage of embryonic cell division
2. Growth rate is constant
3. It represents root growth at tip
4. Represented by expression $L_1=L_0{e}^r$${}^t$

• A. 1 and 3
• B. 2, 3 and 4
• C. 1, 2 and 4
• D. 2 and 3

Answer 1

The correct option is D 2 and 3

Arithmetic growth is a type of growth in which the rate of growth is constant and increase in growth occurs in arithmetic progression. It is found in roots or shoots elongating at a constant rate. Arithmetically diving cells divide in such a fashion that one daughter retains the capacity to divide, while the other grows and differentiates. The process continues. Mathematically it is expressed as
$L_t=L_0+rt$
$L_t$ = length after time t
$L_0$ = length at the beginning
r = growth rate
On plotting growth against time, a linear curve is obtained as shown in the question.

The mitotic cell division during early embryonic development is exponential.
The expression $L_1=L_0{e}^r$${}^t$ represents exponential phase in geometric growth.