Which is the most common mechanism of genetic varisation in the poplulation of a sexually-reproducing organism

Options

A. Recombination
B. Transduction
C. Chromosomal aberrations
D. Genetic drift

Answer

**Step-by-Step Solution:**

1. **Understanding Genetic Variation**: Genetic variation refers to the diversity in gene frequencies among individuals within a population. It is crucial for evolution and adaptation.

2. **Identifying Mechanisms of Genetic Variation**: The question presents four mechanisms:
- Recombination
- Transduction
- Chromosomal Aberration
- Genetic Drift

3. **Analyzing Each Mechanism**:
- **Recombination**: This is the process where genetic material is exchanged between chromosomes during meiosis, leading to new combinations of alleles in gametes. This is a common mechanism in sexually reproducing organisms.
- **Transduction**: This involves the introduction of foreign DNA into a cell via a virus. While it can contribute to genetic variation, it is not the primary mechanism in sexually reproducing organisms.
- **Chromosomal Aberration**: This refers to changes in chromosome structure or number. While it can lead to variation, it is less common compared to recombination.
- **Genetic Drift**: This is a mechanism that causes allele frequencies to change due to random sampling effects, particularly in small populations. It is not a direct mechanism of genetic variation but rather a consequence of it.

4. **Conclusion**: Among the options provided, recombination is the most common mechanism of genetic variation in sexually reproducing organisms because it directly involves the mixing of genetic material during the formation of gametes.

5. **Final Answer**: The most common mechanism of genetic variation in the population of a sexually-reproducing organism is **Recombination**.

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