Which of the following characterizes the lag phase of a normal bacterial growth curve in a closed system?

• A. Cells are dying at a rate faster than they are dividing.
• B. Cells are dividing at their maximum rate.
• C. Cells are metabolically active but not dividing rapidly.
• D. Nutrient levels are depleted and waste products accumulate.

Answer: (C)

Verified step by step guidance

1. Understand the bacterial growth curve phases: lag, log (exponential), stationary, and death phases, each with distinct characteristics.
2. Identify the lag phase as the initial period after bacteria are introduced into a new environment, where cells adapt to conditions but do not divide rapidly yet.
3. Recognize that during the lag phase, cells are metabolically active, synthesizing enzymes and molecules needed for growth, but cell division is minimal or absent.
4. Contrast this with other phases: in the log phase, cells divide at their maximum rate; in the stationary phase, nutrient depletion and waste accumulation slow growth; and in the death phase, cells die faster than they divide.
5. Conclude that the lag phase is best characterized by cells being metabolically active but not dividing rapidly, matching the correct answer.