Significance of meiosis lies in

Options

A. Production of genetic variability
B. Maintaining the number of chromosomes through generations
C. Forming the basis of evolution
D. All of the above

Answer

### Step-by-Step Solution:

1. **Understanding Meiosis**:
- Meiosis is a specialized type of cell division that occurs in sexually reproducing organisms. It reduces the chromosome number by half, resulting in the formation of gametes (sperm and egg cells).

2. **Importance of Genetic Variation**:
- One of the key significances of meiosis is the production of genetic variability. During the process of meiosis, particularly in the pachytene stage, homologous chromosomes undergo a process called crossing over. This involves the exchange of genetic material between homologous chromosomes, resulting in recombinant DNA. This genetic recombination is crucial for introducing variations in the offspring.

3. **Maintenance of Chromosome Number**:
- Meiosis ensures that the chromosome number remains constant across generations. For instance, in humans, each gamete contains 23 chromosomes. When a sperm and an egg fuse during fertilization, they form a zygote with 46 chromosomes (23 from each parent). This process is essential to maintain the species' chromosome number through generations.

4. **Basis of Evolution**:
- Meiosis plays a significant role in evolution. The genetic variations produced through crossing over during meiosis provide the raw material for natural selection. Organisms that can adapt to environmental changes are more likely to survive and reproduce, leading to evolutionary changes over time.

5. **Conclusion**:
- In summary, the significance of meiosis lies in its ability to produce genetic variability, maintain chromosome number, and contribute to evolutionary processes. All these factors are essential for the survival and adaptation of species.