Restoration of haploid phase in the life cycle of sexually reproducing organisms, takes place by

Options

A. Amitosis
B. Mitosis
C. Binary fission
D. Meiosis

Answer

To answer the question regarding the restoration of the haploid phase in the life cycle of sexually reproducing organisms, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Life Cycle**: In sexually reproducing organisms, the life cycle alternates between haploid (n) and diploid (2n) phases. The haploid phase is represented by gametes (sperm and egg cells).

2. **Identifying Cell Division Types**: There are different types of cell division: mitosis, meiosis, and binary fission. Mitosis is a type of cell division that results in two identical diploid cells, while binary fission is primarily seen in unicellular organisms.

3. **Role of Meiosis**: Meiosis is a specialized type of cell division that reduces the chromosome number by half. It is crucial for the formation of gametes. During meiosis, a diploid cell undergoes two rounds of division (meiosis I and meiosis II) to produce four haploid cells.

4. **Restoration of the Haploid Phase**: The restoration of the haploid phase occurs when diploid cells undergo meiosis. This process ensures that the resulting gametes are haploid (n), which is necessary for sexual reproduction.

5. **Conclusion**: Therefore, the correct answer to the question is that the restoration of the haploid phase in the life cycle of sexually reproducing organisms takes place by **meiosis**.

### Final Answer:
The restoration of the haploid phase in the life cycle of sexually reproducing organisms takes place by **meiosis**.

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