Which pair has haploid nature?
(a) Nucellus and antipodal cells
(b) Egg nucleus and secondary nucleus
(c) Megaspore mother cell and antipodal cells
(d) Egg cell and antipodal cells

Options

A. Nucellus and antipodal cells
B. Egg nucleus and secondary nucleus
C. Megaspore mother cell and antipodal cells
D. Egg cell and antipodal cells.

Answer

To determine which pair has haploid nature, we need to analyze each option based on the definition of haploid cells, which contain only one set of chromosomes (N).

### Step-by-Step Solution:

1. **Understanding Haploid Cells**:
- Haploid cells have one set of chromosomes (N). Examples include gametes (sperm and egg cells) and certain cells in plants.

2. **Analyzing Option (a)**: Nucellus and antipodal cells
- **Nucellus**: This is part of the ovule and is diploid (2N).
- **Antipodal cells**: These are haploid (N).
- **Conclusion**: This pair is not haploid because the nucellus is diploid.

3. **Analyzing Option (b)**: Egg nucleus and secondary nucleus
- **Egg nucleus**: This is haploid (N).
- **Secondary nucleus**: This is formed after fertilization and is diploid (2N).
- **Conclusion**: This pair is not haploid because the secondary nucleus is diploid.

4. **Analyzing Option (c)**: Megaspore mother cell and antipodal cells
- **Megaspore mother cell (MMC)**: This is diploid (2N) and undergoes meiosis to produce haploid megaspores.
- **Antipodal cells**: These are haploid (N).
- **Conclusion**: This pair is not haploid because the megaspore mother cell is diploid.

5. **Analyzing Option (d)**: Egg cell and antipodal cells
- **Egg cell**: This is haploid (N).
- **Antipodal cells**: These are also haploid (N).
- **Conclusion**: This pair is haploid because both the egg cell and antipodal cells are haploid.

### Final Answer:
The correct option is **(d) Egg cell and antipodal cells**.

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