Which of the following is not listed as a stage in the biological growth cycle?

• A. Recovery (not listed)
• B. Lag phase
• C. Stationary
• D. Log growth

Answer: (A)

In a microbial growth curve, the cells pass through lag, log (exponential), stationary, and then a death (decline) phase. Recovery isn’t a defined stage in that standard sequence. Lag phase is the adaptation period with little growth, log growth is rapid cell division, and stationary is when growth levels off due to limited nutrients and waste accumulation. The term recovery might describe a temporary resumption after stress in some contexts, but it isn’t one of the formal phases of the growth cycle.