Choose the correct sequence of development of female gametophyte :-

Options

A. Megaspore mother cell (MMC) - Megaspore tetrad megaspore - Nucellus - Female gametophyte
B. Nucellus - MMC - Megaspore tetrad - Megaspore - Female gametophyte
C. Megaspore tetrad - MMC - Megaspore - Nucellus - Female gametophyte
D. Megaspore–MMC–Megaspore tetrad-NucellusFemale gametophyt

Answer

To determine the correct sequence of development of the female gametophyte, we will break down the process step by step:

### Step-by-Step Solution:

1. **Microspore Mother Cell (MMC)**: The process begins with the microspore mother cell, which is a diploid cell located in the ovule. This cell undergoes meiosis to produce haploid megaspores.

2. **Megasporangium Division**: The MMC divides meiotically to form two cells, which is referred to as a megaspore dyad. This is the first stage after the MMC.

3. **Tetrad Formation**: The two cells from the dyad further divide, resulting in a total of four haploid megaspores. This formation of four megaspores is called a tetrad.

4. **Megaspore Development**: Out of the four megaspores formed, typically only one survives and develops further, while the others degenerate.

5. **Nucellus Formation**: The surviving megaspore undergoes mitotic divisions to form the female gametophyte, which is embedded within the nucellus tissue of the ovule.

6. **Formation of Female Gametophyte**: Finally, the development culminates in the formation of the mature female gametophyte (embryo sac), which contains the egg cell and other necessary cells for fertilization.

### Correct Sequence:
- Microspore Mother Cell (MMC) → Megaspore Dyad → Megaspore Tetrad → Surviving Megaspore → Nucellus → Female Gametophyte

### Conclusion:
The correct sequence of development of the female gametophyte is:
**Microspore Mother Cell (MMC) → Megaspore Tetrad → Megaspore → Nucellus → Female Gametophyte.**