A phase where growth slows down due to limited nutrient supply is

Options

A. stationary phase
B. lag phase
C. log phase
D. both (1) and (3)

Answer

**Step-by-Step Solution:**

1. **Understanding Growth Phases**: In biological systems, particularly in the growth of cells or organisms, there are distinct phases of growth that occur in response to nutrient availability and waste accumulation.

2. **Identifying the Phases**:
- **Lag Phase**: This is the initial phase where cells are adapting to their environment. Nutrients are being consumed, but growth has not yet started. Therefore, this phase is not characterized by slowed growth due to limited nutrients.
- **Log Phase**: Following the lag phase, cells enter the log phase (or exponential phase) where they grow rapidly due to the availability of nutrients. This phase is marked by active cell division and growth, not a slowdown.
- **Stationary Phase**: This phase occurs when the growth rate slows down and stabilizes. It happens when nutrients become limited and waste products accumulate. In this phase, the number of dying cells equals the number of new cells being produced, leading to a plateau in growth.

3. **Evaluating the Options**:
- **Option 1: Stationary Phase** - This is the correct answer as it describes the phase where growth slows down due to limited nutrient supply.
- **Option 2: Lag Phase** - Incorrect, as this phase is characterized by no growth rather than slowed growth.
- **Option 3: Log Phase** - Incorrect, as this phase is characterized by rapid growth.
- **Option 4: Both 1 and 3** - Incorrect, since log phase does not represent slowed growth.

4. **Conclusion**: The correct answer to the question is **Option 1: Stationary Phase**, where growth slows down due to limited nutrient supply and the accumulation of waste products.

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