Meiosis in diploid organisms results in

Options

A. (a) production of gametes
B. (b) reduction in the number of chromosomes
C. (c) introduction of variation
D. (d) all of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Meiosis**: Meiosis is a specialized type of cell division that occurs in diploid organisms, specifically in germ cells, which are responsible for producing gametes (sperm and eggs).

2. **Reduction of Chromosome Number**: One of the key features of meiosis is that it reduces the chromosome number by half. A diploid cell (2n) undergoes meiosis to produce haploid cells (n). For example, if the diploid organism has 46 chromosomes, the resulting gametes will each have 23 chromosomes.

3. **Stages of Meiosis**: Meiosis consists of two sequential divisions: Meiosis I and Meiosis II.
- **Meiosis I**: This is the reductional division where homologous chromosomes are separated. During this phase, crossing over can occur, which is the exchange of genetic material between homologous chromosomes, leading to genetic variation.
- **Meiosis II**: This is similar to mitosis, where the sister chromatids are separated, resulting in a total of four haploid daughter cells.

4. **Production of Gametes**: The end result of meiosis is the production of four haploid gametes from one diploid germ cell. These gametes are essential for sexual reproduction.

5. **Introduction of Variation**: Due to the crossing over and independent assortment of chromosomes during meiosis, genetic variation is introduced in the offspring, which is crucial for evolution and adaptation.

6. **Conclusion**: Therefore, meiosis in diploid organisms results in the production of gametes, reduction in the number of chromosomes, and introduction of genetic variation.

**Final Answer**: Meiosis in diploid organisms results in **all of the above**: production of gametes, reduction in the number of chromosomes, and introduction of variation.

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