The chromosome number in meiocyte of an adder`s tongue fern is

Options

A. 380
B. 630
C. 660
D. 1260

Answer

To determine the chromosome number in the meiocyte of an adder's tongue fern (Ophioglossum), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Meiocytes**: Meiocytes are specialized cells that undergo meiosis to produce haploid spores. In ferns, meiocytes are typically diploid (2N) and will produce haploid spores (N) after meiosis.

2. **Chromosome Count in Ophioglossum**: The adder's tongue fern, also known as Ophioglossum, is notable for having the highest number of chromosomes among all known plants. Specifically, it has 630 pairs of chromosomes.

3. **Calculating Total Chromosomes**: Since each pair consists of two chromosomes, we can calculate the total number of chromosomes in the diploid state:
\[ \text{Total chromosomes} = \text{Number of pairs} \times 2 = 630 \times 2 = 1260 \]

4. **Identifying Meiocyte Chromosome Number**: Since meiocytes are diploid in nature, the chromosome number in the meiocyte of the adder's tongue fern is 1260.

5. **Conclusion**: The chromosome number in the meiocyte of the adder's tongue fern (Ophioglossum) is 1260.

### Final Answer:
The chromosome number in the meiocyte of an adder's tongue fern is **1260**.

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