The number of chromosome groups at the equatorial plate in metaphase-I of meiosis in a plant with 2n=50 shall be

Options

A. 25
B. 50
C. 100
D. 75

Answer

To solve the question regarding the number of chromosome groups at the equatorial plate in metaphase-I of meiosis in a plant with 2n=50, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Chromosome Number**:
- The given chromosome number is 2n = 50. This means that the diploid number of chromosomes in the plant is 50.

2. **Determine the Haploid Number**:
- Since 2n represents the diploid number, to find the haploid number (n), we divide by 2:
\[ n = \frac{2n}{2} = \frac{50}{2} = 25 \]
- Therefore, the haploid number of chromosomes is 25.

3. **Meiosis Overview**:
- Meiosis consists of two main stages: Meiosis I and Meiosis II. In Meiosis I, homologous chromosomes are separated, and in Meiosis II, sister chromatids are separated.

4. **Focus on Metaphase I**:
- During Metaphase I of meiosis, homologous chromosomes (which are pairs) align at the equatorial plate. Each pair consists of two chromosomes.

5. **Calculate the Number of Chromosome Groups**:
- Since we have 25 chromosomes in the haploid set (n = 25), during Metaphase I, these chromosomes will align in pairs.
- Therefore, the number of chromosome groups (pairs) at the equatorial plate during Metaphase I will be:
\[ \text{Number of chromosome groups} = n = 25 \]

6. **Conclusion**:
- The number of chromosome groups at the equatorial plate in Metaphase I of meiosis in a plant with 2n = 50 is 25.

### Final Answer:
The number of chromosome groups at the equatorial plate in metaphase-I of meiosis in a plant with 2n = 50 shall be **25**.

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