Ques. 1AIPMT 2004
The maximum growth rate occurs in :-
- Exponential phase
- Stationary phase
- Senescent phase
- Lag phase
Answer
(1) Exponential phase
Solution
As per NCERT, a plot of growth against time gives a sigmoid (S-shaped) curve with a lag phase, an exponential (log) phase and a stationary phase.
∵ In the exponential phase all progeny cells keep dividing (geometric growth),
∴ the growth rate is maximum in this phase; growth is slow in the lag phase and slows down / stops in the stationary and senescent phases.
Answer: (1)