Reproductive value of an individual is greatest just before

Options

A. first reproduction
B. death
C. birth
D. marriage

Answer

To determine when the reproductive value of an individual is greatest, we need to understand the concept of reproductive value itself. Reproductive value refers to the potential contribution of an individual to the future generations of a population, which is influenced by its age and reproductive status.

### Step-by-Step Solution:

1. **Define Reproductive Value**:
- Reproductive value is a measure of the expected future reproduction of an individual. It indicates how many offspring an individual is likely to produce in its lifetime.

2. **Consider the Life Cycle of Organisms**:
- Organisms go through various stages in their life cycle, including juvenile, adult, and senescent (old) stages. The reproductive value changes at different stages.

3. **Identify Key Life Stages**:
- **Just Before First Reproduction**: This is the stage just before an individual is capable of reproducing for the first time. At this point, the individual has not yet reproduced but is about to enter the reproductive phase.
- **Just Before Death**: As individuals approach death, their ability to reproduce decreases, leading to a lower reproductive value.
- **Just Before Birth**: This stage refers to the time just before an individual is born, which does not apply to reproductive value in the context of the individual itself.
- **Just Before Marriage**: This option is irrelevant in biological terms, as marriage does not have a direct link to reproduction in the context of organisms.

4. **Evaluate Each Option**:
- **Just Before First Reproduction**: This is when the reproductive value is at its peak because the individual is about to start reproducing.
- **Just Before Death**: The reproductive value is low as the individual can no longer contribute offspring.
- **Just Before Birth**: This does not pertain to the reproductive value of the individual in question.
- **Just Before Marriage**: This is not applicable in biological reproduction terms.

5. **Conclusion**:
- The reproductive value of an individual is greatest just before its first reproduction. This is when the individual is at the threshold of contributing to the next generation.

### Final Answer:
The reproductive value of an individual is greatest just before first reproduction.

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