Question

The total time in which growth occurs is called
A. Phase of maturation
B. The phase of cell division
C. Phase of elongation
D. Grand period of growth

Answer 1

Hint: Total time in which growth occurs is related to the rapid increase in size or number in the cells of organisms. The growth rate is maximum during this period. It starts just after the lag phase.

Complete answer: Growth: Growth refers to an irreversible change in size, number, or shape of the cells, organism, and organ. All organisms do not show the same type of growth e.g. plants show diffuse and unlimited growth, whereas animals show uniform and limited growth.
-Grand period of growth: During this period there is a rapid increase in the number, size, and volume of plants. This period starts with slow growth then rapid growth and again slowdown in growth. But the growth in this period is maximum. The growth in a plant can be depicted by the growth curve.
-Growth curve: Plants show growth throughout their lifespan, but the rate of growth is not always the same, Sometime it is very fast sometimes it is very low. By plotting an increase in cell number (growth) with the time, we give us a sigmoid-shaped curve called a growth curve. This curve has three phases:-
-Lag phase: This is the first phase in growth, in this phase growth is slow. It is a preparatory phase for the subsequent growth phase.
-Log phase: log / exponential phase in this phase the cells divide rapidly. the number of cells increases very fast.
-Stationary phase: In this phase growth rate starts decreasing and finally stops due to limiting factors. Limiting factors are the exhaustion of space, exhaustion of nutrients, and the production of certain stop factors by cells itself.
-Grand period of growth: It is the period during which cell, organ, and plant develop slowly, during this period there is a rapid increase in number, size, and volume of plant. This period starts with slow growth then rapid growth and again slowdown in growth. But the growth in this period is maximum.

Hence, the correct answer is Option D.
Additional information:
The growth of the organism depends on many factors such as resources, space, and nutrients. After the stationary phase there comes the death period in which this cell dies.

Note: Phase of cell division comes under the log phase while the phase of maturation and elongation comes under the stationary phase. In the lag phase, the plant prepares itself for the exponential growth phase.