The phase of the population growth where natality is equal to mortality is called

Options

A. Asymptote
B. lag phase
C. Log phase
D. none of these

Answer

To answer the question about the phase of population growth where natality is equal to mortality, we can follow these steps:

### Step-by-Step Solution:

1. **Define Natality and Mortality**:
- Natality refers to the number of births in a population over a specific period, usually expressed per thousand individuals.
- Mortality refers to the number of deaths in a population over the same period, also expressed per thousand individuals.

2. **Understand the Context of Population Growth**:
- In population dynamics, different phases of growth can be observed, such as exponential growth, logistic growth, and stable phases.

3. **Identify the Phase Where Natality Equals Mortality**:
- When natality equals mortality, it indicates that the number of births is balancing out the number of deaths. This leads to a stable population size where there is no net increase or decrease in the population.

4. **Analyze the Options Given**:
- The options provided are "asymptotic phase," "log phase," and "none of this."
- The asymptotic phase refers to a condition where the population size stabilizes and does not change significantly over time, which aligns with the condition where natality equals mortality.
- The log phase (or logistic phase) is characterized by rapid growth, where births exceed deaths significantly.

5. **Conclusion**:
- Based on the definitions and analysis, the correct answer to the question is the "asymptotic phase," where natality is equal to mortality.

### Final Answer:
The phase of population growth where natality is equal to mortality is called the **asymptotic phase**.

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