Question

Can you think of more similar examples of sigmoid growth curve?What kind of a curve can you expect in a tree showing seasonal activities?(This question is in reference to NCERT Class 11 Pg.243).Thank You.

Answer 1

Sigmoid growth curve is typical of cells in culture, higher plants and plant organs. So kind of a growth curve expected in a tree showing seasonal activities is also sigmoid curve. Trees like deciduous

Answer 2

The sigmoid growth curve is an S-shaped growth curve. It contains 3 stages: Lag phage, Log phage or Exponential phage, Stationary phage

Explanation:

A similar example of sigmoid growth curve is a bacterial growth curve in a closed container of media (containing essential components for bacterial growth). (Bacterial growth curve images is attached)

• Bacteria first grow in lag phage- in this initial phage bacterial growth is very slow. Bacterial cell increase in size, cell division not occurs.

• Log phage- after lag phase, they enter in the log phase. Now bacterial cells are dividing by binary fission, and the growth rate is high.

• Stationary phage- In this stage the rate of cell division and the rate of cell death is equal. Because the amount of available nutrients is decreased and waste products start to accumulate. So the result is no overall growth of population.

• Death phage- In this stage, the number of dying cells is increased for decreasing nutrient amounts and increasing waste products.  

A tree is showing “sigmoid Growth Curve” during its seasonal activities. Because tree also has four stages like a sigmoid growth curve.

1. Lag phase- The time of spring season when plants leave starts growing.
2. Exponential phase- the time of the summer season.
3. Stationary phage - the time of winter season .