Question

Which one of the following occurs maximum during exponential growth phase in plants?

• A. Cell formation
• B. Cell elongation
• C. Cell differentiation
• D. Cell dedifferentiation

Hint:

Exponential phase = Rapid increase in size, mainly due to cell elongation, not just cell division.

Answer 1

The Correct Option is B

Concept:
Plant growth follows a sigmoid (S-shaped) growth curve consisting of three phases:
• Lag phase → Slow growth
• Exponential (log) phase → Rapid growth
• Stationary phase → Growth slows/stops The exponential phase is characterized by maximum increase in size due to rapid cellular activities.

Step 1: Understand what happens in exponential phase. During this phase, cells rapidly increase in size, leading to a sharp rise in growth rate. This is mainly due to extensive cell elongation.

Step 2: Differentiate between the processes.
• Cell formation → Occurs in meristematic region but not the main contributor here
• Cell elongation → Major contributor to rapid increase in size \checkmark
• Cell differentiation → Occurs after elongation phase $\times$
• Cell dedifferentiation → Special process, not related to growth phase $\times$

Step 3: Conclusion. Thus, the process occurring maximum during exponential growth phase is: \[ \text{Cell elongation} \]