When growth is going on at a slow rate, this phase is known as

Options

A. (a) lag period
B. (b) log period
C. (c) period of diminishing growth
D. (d) exponential phase

Answer

**Step-by-Step Solution:**

1. **Understanding Growth Phases**: In the context of bacterial growth, there are four main phases: lag phase, log phase, stationary phase, and death phase. Each phase has distinct characteristics regarding cell division and growth rate.

2. **Identifying the Lag Phase**: The lag phase is characterized by a slow rate of growth. During this phase, bacteria do not divide immediately; instead, they prepare for upcoming cell division by synthesizing proteins and enzymes necessary for growth.

3. **Distinguishing Between Phases**:
- **Log Phase**: This phase is also known as the exponential phase, where the growth rate is at its maximum, and active cell division occurs.
- **Stationary Phase**: In this phase, the growth rate levels off, and no new cells are produced as the number of living cells equals the number of dying cells.
- **Death Phase**: This phase is characterized by a decline in the number of viable cells as they begin to die off.

4. **Conclusion**: Since the question specifies a phase where growth is occurring at a slow rate, this corresponds to the lag phase. Therefore, the answer is the lag phase.

**Final Answer**: The phase when growth is going on at a slow rate is known as the **lag phase**.

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